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1.
PLoS Genet ; 19(5): e1010655, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37163495

RESUMO

The photoperiodic response is critical for plants to adjust their reproductive phase to the most favorable season. Wheat heads earlier under long days (LD) than under short days (SD) and this difference is mainly regulated by the PHOTOPERIOD1 (PPD1) gene. Tetraploid wheat plants carrying the Ppd-A1a allele with a large deletion in the promoter head earlier under SD than plants carrying the wildtype Ppd-A1b allele with an intact promoter. Phytochromes PHYB and PHYC are necessary for the light activation of PPD1, and mutations in either of these genes result in the downregulation of PPD1 and very late heading time. We show here that both effects are reverted when the phyB mutant is combined with loss-of-function mutations in EARLY FLOWERING 3 (ELF3), a component of the Evening Complex (EC) in the circadian clock. We also show that the wheat ELF3 protein interacts with PHYB and PHYC, is rapidly modified by light, and binds to the PPD1 promoter in planta (likely as part of the EC). Deletion of the ELF3 binding region in the Ppd-A1a promoter results in PPD1 upregulation at dawn, similar to PPD1 alleles with intact promoters in the elf3 mutant background. The upregulation of PPD1 is correlated with the upregulation of the florigen gene FLOWERING LOCUS T1 (FT1) and early heading time. Loss-of-function mutations in PPD1 result in the downregulation of FT1 and delayed heading, even when combined with the elf3 mutation. Taken together, these results indicate that ELF3 operates downstream of PHYB as a direct transcriptional repressor of PPD1, and that this repression is relaxed both by light and by the deletion of the ELF3 binding region in the Ppd-A1a promoter. In summary, the regulation of the light mediated activation of PPD1 by ELF3 is critical for the photoperiodic regulation of wheat heading time.


Assuntos
Fitocromo B , Triticum , Fitocromo B/genética , Fitocromo B/metabolismo , Triticum/genética , Flores/genética , Flores/metabolismo , Ritmo Circadiano/genética , Fotoperíodo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(19): e2300203120, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126674

RESUMO

Plant height is an important agronomic trait with a significant impact on grain yield, as demonstrated by the positive effect of the REDUCED HEIGHT (RHT) dwarfing alleles (Rht1b) on lodging and harvest index in the "Green Revolution" wheat varieties. However, these gibberellic acid (GA)-insensitive alleles also reduce coleoptile length, biomass production, and yield potential in some environments, triggering the search for alternative GA-sensitive dwarfing genes. Here we report the identification, validation, and characterization of the gene underlying the GA-sensitive dwarfing locus RHT25 in wheat. This gene, designated as PLATZ-A1 (TraesCS6A02G156600), is expressed mainly in the elongating stem and developing spike and encodes a plant-specific AT-rich sequence- and zinc-binding protein (PLATZ). Natural and induced loss-of-function mutations in PLATZ-A1 reduce plant height and its overexpression increases plant height, demonstrating that PLATZ-A1 is the causative gene of RHT25. PLATZ-A1 and RHT1 show a significant genetic interaction on plant height, and their encoded proteins interact with each other in yeast and wheat protoplasts. These results suggest that PLATZ1 can modulate the effect of DELLA on wheat plant height. We identified four natural truncation mutations and one promoter insertion in PLATZ-A1 that are more frequent in modern varieties than in landraces, suggesting positive selection during wheat breeding. These mutations can be used to fine-tune wheat plant height and, in combination with other GA-sensitive dwarfing genes, to replace the GA-insensitive Rht1b alleles and search for grain yield improvements beyond those of the Green Revolution varieties.


Assuntos
Melhoramento Vegetal , Triticum , Triticum/genética , Fatores de Transcrição/metabolismo , Giberelinas/metabolismo , Proteínas de Plantas/genética
3.
Plant J ; 118(2): 519-533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38184778

RESUMO

Precise regulation of flowering time is critical for cereal crops to synchronize reproductive development with optimum environmental conditions, thereby maximizing grain yield. The plant-specific gene GIGANTEA (GI) plays an important role in the control of flowering time, with additional functions on the circadian clock and plant stress responses. In this study, we show that GI loss-of-function mutants in a photoperiod-sensitive tetraploid wheat background exhibit significant delays in heading time under both long-day (LD) and short-day photoperiods, with stronger effects under LD. However, this interaction between GI and photoperiod is no longer observed in isogenic lines carrying either a photoperiod-insensitive allele in the PHOTOPERIOD1 (PPD1) gene or a loss-of-function allele in EARLY FLOWERING 3 (ELF3), a known repressor of PPD1. These results suggest that the normal circadian regulation of PPD1 is required for the differential effect of GI on heading time in different photoperiods. Using crosses between mutant or transgenic plants of GI and those of critical genes in the flowering regulation pathway, we show that GI accelerates wheat heading time by promoting FLOWERING LOCUS T1 (FT1) expression via interactions with ELF3, VERNALIZATION 2 (VRN2), CONSTANS (CO), and the age-dependent microRNA172-APETALA2 (AP2) pathway, at both transcriptional and protein levels. Our study reveals conserved GI mechanisms between wheat and Arabidopsis but also identifies specific interactions of GI with the distinctive photoperiod and vernalization pathways of the temperate grasses. These results provide valuable knowledge for modulating wheat heading time and engineering new varieties better adapted to a changing environment.


Assuntos
Relógios Circadianos , Triticum , Triticum/fisiologia , Flores , Fotoperíodo , Genes de Plantas/genética , Relógios Circadianos/genética , Regulação da Expressão Gênica de Plantas/genética
4.
PLoS Genet ; 18(4): e1010157, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35468125

RESUMO

Plants possess regulatory mechanisms that allow them to flower under conditions that maximize reproductive success. Selection of natural variants affecting those mechanisms has been critical in agriculture to modulate the flowering response of crops to specific environments and to increase yield. In the temperate cereals, wheat and barley, the photoperiod and vernalization pathways explain most of the natural variation in flowering time. However, other pathways also participate in fine-tuning the flowering response. In this work, we integrate the conserved microRNA miR172 and its targets APETALA2-like (AP2L) genes into the temperate grass flowering network involving VERNALIZATION 1 (VRN1), VRN2 and FLOWERING LOCUS T 1 (FT1 = VRN3) genes. Using mutants, transgenics and different growing conditions, we show that miR172 promotes flowering in wheat, while its target genes AP2L1 (TaTOE1) and AP2L5 (Q) act as flowering repressors. Moreover, we reveal that the miR172-AP2L pathway regulates FT1 expression in the leaves, and that this regulation is independent of VRN2 and VRN1. In addition, we show that the miR172-AP2L module and flowering are both controlled by plant age through miR156 in spring cultivars. However, in winter cultivars, flowering and the regulation of AP2L1 expression are decoupled from miR156 downregulation with age, and induction of VRN1 by vernalization is required to repress AP2L1 in the leaves and promote flowering. Interestingly, the levels of miR172 and both AP2L genes modulate the flowering response to different vernalization treatments in winter cultivars. In summary, our results show that conserved and grass specific gene networks interact to modulate the flowering response, and that natural or induced mutations in AP2L genes are useful tools for fine-tuning wheat flowering time in a changing environment.


Assuntos
Genes de Plantas , Triticum , Flores/genética , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Poaceae/genética , Triticum/genética
5.
PLoS Genet ; 18(1): e1009747, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025863

RESUMO

Improving our understanding of the genes regulating grain yield can contribute to the development of more productive wheat varieties. Previously, a highly significant QTL affecting spikelet number per spike (SNS), grain number per spike (GNS) and grain yield was detected on chromosome arm 7AL in multiple genome-wide association studies. Using a high-resolution genetic map, we established that the A-genome homeolog of WHEAT ORTHOLOG OF APO1 (WAPO-A1) was a leading candidate gene for this QTL. Using mutants and transgenic plants, we demonstrate in this study that WAPO-A1 is the causal gene underpinning this QTL. Loss-of-function mutants wapo-A1 and wapo-B1 showed reduced SNS in tetraploid wheat, and the effect was exacerbated in wapo1 combining both mutations. By contrast, spikes of transgenic wheat plants carrying extra copies of WAPO-A1 driven by its native promoter had higher SNS, a more compact spike apical region and a smaller terminal spikelet than the wild type. Taken together, these results indicate that WAPO1 affects SNS by regulating the timing of terminal spikelet formation. Both transgenic and wapo1 mutant plants showed a wide range of floral abnormalities, indicating additional roles of WAPO1 on wheat floral development. Previously, we found three widespread haplotypes in the QTL region (H1, H2 and H3), each associated with particular WAPO-A1 alleles. Results from this and our previous study show that the WAPO-A1 allele in the H1 haplotype (115-bp deletion in the promoter) is expressed at significantly lower levels in the developing spikes than the alleles in the H2 and H3 haplotypes, resulting in reduced SNS. Field experiments also showed that the H2 haplotype is associated with the strongest effects in increasing SNS and GNS (H2>H3>H1). The H2 haplotype is already present in most modern common wheat varieties but is rare in durum wheat, where it might be particularly useful to improve grain yield.


Assuntos
Mapeamento Cromossômico/métodos , Proteínas de Plantas/genética , Locos de Características Quantitativas , Triticum/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Ligação Genética , Haplótipos , Mutação com Perda de Função , Deleção de Sequência , Triticum/genética
6.
Plant Cell ; 33(12): 3621-3644, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34726755

RESUMO

Inflorescence architecture is an important determinant of crop productivity. The number of spikelets produced by the wheat inflorescence meristem (IM) before its transition to a terminal spikelet (TS) influences the maximum number of grains per spike. Wheat MADS-box genes VERNALIZATION 1 (VRN1) and FRUITFULL 2 (FUL2) (in the SQUAMOSA-clade) are essential to promote the transition from IM to TS and for spikelet development. Here we show that SQUAMOSA genes contribute to spikelet identity by repressing MADS-box genes VEGETATIVE TO REPRODUCTIVE TRANSITION 2 (VRT2), SHORT VEGETATIVE PHASE 1 (SVP1), and SVP3 in the SVP clade. Constitutive expression of VRT2 resulted in leafy glumes and lemmas, reversion of spikelets to spikes, and downregulation of MADS-box genes involved in floret development, whereas the vrt2 mutant reduced vegetative characteristics in spikelets of squamosa mutants. Interestingly, the vrt2 svp1 mutant showed similar phenotypes to squamosa mutants regarding heading time, plant height, and spikelets per spike, but it exhibited unusual axillary inflorescences in the elongating stem. We propose that SQUAMOSA-SVP interactions are important to promote heading, formation of the TS, and stem elongation during the early reproductive phase, and that downregulation of SVP genes is then necessary for normal spikelet and floral development. Manipulating SVP and SQUAMOSA genes can contribute to engineering spike architectures with improved productivity.


Assuntos
Meristema/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Triticum/genética , Meristema/crescimento & desenvolvimento , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Triticum/crescimento & desenvolvimento
7.
Molecules ; 29(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611749

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with a high degree of malignancy and poor prognosis. Tumor-associated macrophages (TAMs) have been identified as significant contributors to the growth and metastasis of TNBC through the secretion of various growth factors and chemokines. Salvianolic acid A (SAA) has been shown to have anti-cancer activities. However, the potential activity of SAA on re-polarized TAMs remains unclear. As there is a correlation between the TAMs and TNBC, this study investigates the effect of SAA on TAMs in the TNBC microenvironment. For that purpose, M2 TAM polarization was induced by two kinds of TNBC-conditioned medium (TNBC-TCM) in the absence or presence of SAA. The gene and protein expression of TAM markers were analyzed by qPCR, FCM, IF, ELISA, and Western blot. The protein expression levels of ERK and p-ERK in M2-like TAMs were analyzed by Western blot. The migration and invasion properties of M2-like TAMs were analyzed by Transwell assays. Here, we demonstrated that SAA increased the expression levels of CD86, IL-1ß, and iNOS in M2-like TAMs and, conversely, decreased the expression levels of Arg-1 and CD206. Moreover, SAA inhibited the migration and invasion properties of M2-like TAMs effectively and decreased the protein expression of TGF-ß1 and p-ERK in a concentration-dependent manner, as well as TGF-ß1 gene expression and secretion. Our current findings for the first time demonstrated that SAA inhibits macrophage polarization to M2-like TAMs by inhibiting the ERK pathway and promotes M2-like TAM re-polarization to the M1 TAMs, which may exert its anti-tumor effect by regulating M1/M2 TAM polarization. These findings highlight SAA as a potential regulator of M2 TAMs and the possibility of utilizing SAA to reprogram M2 TAMs offers promising insights for the clinical management of TNBC.


Assuntos
Ácidos Cafeicos , Lactatos , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Fator de Crescimento Transformador beta1 , Microambiente Tumoral , Macrófagos Associados a Tumor
8.
PLoS Genet ; 16(7): e1008812, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658893

RESUMO

In Arabidopsis, CONSTANS (CO) integrates light and circadian clock signals to promote flowering under long days (LD). In the grasses, a duplication generated two paralogs designated as CONSTANS1 (CO1) and CONSTANS2 (CO2). Here we show that in tetraploid wheat plants grown under LD, combined loss-of-function mutations in the A and B-genome homeologs of CO1 and CO2 (co1 co2) result in a small (3 d) but significant (P<0.0001) acceleration of heading time both in PHOTOPERIOD1 (PPD1) sensitive (Ppd-A1b, functional ancestral allele) and insensitive (Ppd-A1a, functional dominant allele) backgrounds. Under short days (SD), co1 co2 mutants headed 13 d earlier than the wild type (P<0.0001) in the presence of Ppd-A1a. However, in the presence of Ppd-A1b, spikes from both genotypes failed to emerge by 180 d. These results indicate that CO1 and CO2 operate mainly as weak heading time repressors in both LD and SD. By contrast, in ppd1 mutants with loss-of-function mutations in both PPD1 homeologs, the wild type Co1 allele accelerated heading time >60 d relative to the co1 mutant allele under LD. We detected significant genetic interactions among CO1, CO2 and PPD1 genes on heading time, which were reflected in complex interactions at the transcriptional and protein levels. Loss-of-function mutations in PPD1 delayed heading more than combined co1 co2 mutations and, more importantly, PPD1 was able to perceive and respond to differences in photoperiod in the absence of functional CO1 and CO2 genes. Similarly, CO1 was able to accelerate heading time in response to LD in the absence of a functional PPD1. Taken together, these results indicate that PPD1 and CO1 are able to respond to photoperiod in the absence of each other, and that interactions between these two photoperiod pathways at the transcriptional and protein levels are important to fine-tune the flowering response in wheat.


Assuntos
Epistasia Genética/genética , Fotoperíodo , Proteínas de Plantas/genética , Triticum/genética , Alelos , Arabidopsis , Relógios Circadianos/genética , Ritmo Circadiano/genética , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Genótipo , Fatores de Transcrição/genética , Triticum/crescimento & desenvolvimento
9.
Development ; 146(14)2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337701

RESUMO

The spikelet is the basic unit of the grass inflorescence. In this study, we show that wheat MADS-box genes VRN1, FUL2 and FUL3 play critical and redundant roles in spikelet and spike development, and also affect flowering time and plant height. In the vrn1ful2ful3-null triple mutant, the inflorescence meristem formed a normal double-ridge structure, but then the lateral meristems generated vegetative tillers subtended by leaves instead of spikelets. These results suggest an essential role of these three genes in the fate of the upper spikelet ridge and the suppression of the lower leaf ridge. Inflorescence meristems of vrn1ful2ful3-null and vrn1ful2-null remained indeterminate and single vrn1-null and ful2-null mutants showed delayed formation of the terminal spikelet and increased number of spikelets per spike. Moreover, the ful2-null mutant showed more florets per spikelet, which together with a higher number of spikelets, resulted in a significant increase in the number of grains per spike in the field. Our results suggest that a better understanding of the mechanisms underlying wheat spikelet and spike development can inform future strategies to improve grain yield in wheat.


Assuntos
Inflorescência/crescimento & desenvolvimento , Inflorescência/genética , Proteínas de Plantas/fisiologia , Triticum/crescimento & desenvolvimento , Triticum/genética , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas/fisiologia , Proteínas de Domínio MADS/genética , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Repressoras/genética
10.
Plant Physiol ; 186(2): 1060-1073, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33734397

RESUMO

Seed setting rate is one of the critical factors that determine rice yield. Grain formation is a complex biological process, whose molecular mechanism is yet to be improved. Here we investigated the function of an OVATE family protein, Embryo Sac Development 1 (ESD1), in the regulation of seed setting rate in rice (Oryza sativa) by examining its loss-of-function mutants generated via clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated9 (Cas9) technology. ESD1 was predominantly expressed at Stage 6 of panicle development, especially in the ovules. esd1 mutants displayed reduced seed setting rates with normal stamen development and pollen tube growth but abnormal pistil group. Investigation of embryo sacs revealed that during the mitosis of functional megaspores, some egg cells degraded during differentiation in esd1 mutants, thereby hindering subsequent fertilization process and reducing seed setting rate. In addition, the transcriptional level of O. sativa anaphase-promoting complex 6, a reported embryo sac developing gene, was significantly reduced in esd1 mutants. These results support that ESD1 is an important modulator of ESD and seed setting rate in rice. Together, this finding demonstrates that ESD1 positively regulates the seed setting rate by controlling ESD in rice and has implications for the improvement of rice yield.


Assuntos
Oryza/genética , Proteínas de Plantas/metabolismo , Flores/embriologia , Flores/genética , Mutação com Perda de Função , Oryza/embriologia , Óvulo Vegetal/embriologia , Óvulo Vegetal/genética , Proteínas de Plantas/genética , Tubo Polínico/embriologia , Tubo Polínico/genética , Polinização , Sementes/embriologia , Sementes/genética
11.
Plant Biotechnol J ; 19(2): 251-260, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32741081

RESUMO

Heterosis utilization is the most effective way to improve rice yields. The cytoplasmic male-sterility (CMS) and photoperiod/thermosensitive genic male-sterility (PTGMS) systems have been widely used in rice production. However, the rate of resource utilization for the CMS system hybrid rice is low, and the hybrid seed production for the PTGMS system is affected by the environment. The technical limitations of these two breeding methods restrict the rapid development of hybrid rice. The advantages of the genic male-sterility (GMS) rice, such as stable sterility and free combination, can fill the gaps of the first two generations of hybrid rice technology. At present, the third-generation hybrid rice breeding technology is being used to realize the application of GMS materials in hybrid rice. This study aimed to use an artificial CMS gene as a pollen killer to create a smart sterile line for hybrid rice production. The clustered regularly interspaced short palindromic repeats/CRISPR-associated 9 (CRISPR/Cas9) technology was used to successfully obtain a CYP703A3-deficient male-sterile mutant containing no genetically modified component in the genetic background of indica 9311. Through young ear callus transformation, this mutant was transformed with three sets of element-linked expression vectors, including pollen fertility restoration gene CYP703A3, pollen-lethality gene orfH79 and selection marker gene DsRed2. The maintainer 9311-3B with stable inheritance was obtained, which could realize the batch breeding of GMS materials. Further, the sterile line 9311-3A and restorer lines were used for hybridization, and a batch of superior combinations of hybrid rice was obtained.


Assuntos
Oryza , Infertilidade das Plantas/genética , Oryza/genética , Melhoramento Vegetal , Tecnologia
12.
J Exp Bot ; 70(1): 193-204, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295847

RESUMO

FLOWERING LOCUS T2 (FT2) is the closest paralog of the FT1 flowering gene in the temperate grasses. Here we show that overexpression of FT2 in Brachypodium distachyon and barley results in precocious flowering and reduced spikelet number, while down-regulation by RNA interference results in delayed flowering and a reduced percentage of filled florets. Similarly, truncation mutations of FT2 homeologs in tetraploid wheat delayed flowering (2-4 d) and reduced fertility. The wheat ft2 mutants also showed a significant increase in the number of spikelets per spike, with a longer spike development period potentially contributing to the delayed heading time. In the wheat leaves, FT2 was expressed later than FT1, suggesting a relatively smaller role for FT2 in the initiation of the reproductive phase. FT2 transcripts were detected in the shoot apical meristem and increased during early spike development. Transversal sections of the developing spike showed the highest FT2 transcript levels in the distal part, where new spikelets are formed. Our results suggest that, in wheat, FT2 plays an important role in spike development and fertility and a limited role in the timing of the transition between the vegetative and reproductive shoot apical meristem.


Assuntos
Brachypodium/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Proteínas de Plantas/genética , Triticum/genética , Brachypodium/crescimento & desenvolvimento , Fertilidade/genética , Flores/genética , Genes de Plantas/genética , Hordeum/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Reprodução/genética , Triticum/crescimento & desenvolvimento
13.
Plant Physiol ; 174(2): 1139-1150, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28408541

RESUMO

Plants utilize variation in day length (photoperiod) to anticipate seasonal changes. They respond by modulating their growth and development to maximize seed production, which in cereal crops is directly related to yield. In wheat (Triticum aestivum), the acceleration of flowering under long days (LD) is dependent on the light induction of PHOTOPERIOD1 (PPD1) by phytochromes. Under LD, PPD1 activates FLOWERING LOCUS T1 (FT1), a mobile signaling protein that travels from the leaves to the shoot apical meristem to promote flowering. Here, we show that the interruption of long nights by short pulses of light ("night-break" [NB]) accelerates wheat flowering, suggesting that the duration of the night is critical for wheat photoperiodic response. PPD1 transcription was rapidly upregulated by NBs, and the magnitude of this induction increased with the length of darkness preceding the NB Cycloheximide abolished the NB up-regulation of PPD1, suggesting that this process is dependent on active protein synthesis during darkness. While one NB was sufficient to induce PPD1, more than 15 NBs were required to induce high levels of FT1 expression and a strong acceleration of flowering. Multiple NBs did not affect the expression of core circadian clock genes. The acceleration of flowering by NB disappeared in ppd1-null mutants, demonstrating that this response is mediated by PPD1 The acceleration of flowering was strongest when NBs were applied in the middle of the night, suggesting that in addition to PPD1, other circadian-controlled factors are required for the up-regulation of FT1 expression and the acceleration of flowering.


Assuntos
Escuridão , Flores/fisiologia , Fotoperíodo , Proteínas de Plantas/metabolismo , Triticum/fisiologia , Alelos , Relógios Circadianos/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Modelos Biológicos , Fitocromo/metabolismo , Proteínas de Plantas/genética , Biossíntese de Proteínas , Fatores de Tempo , Transcrição Gênica , Triticum/genética
14.
AJR Am J Roentgenol ; 208(5): 1116-1126, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28301223

RESUMO

OBJECTIVE: The aim of the present study is to investigate the biologic effects of internal irradiation and the therapeutic effectiveness of 131I-labeled arginine-glycine-aspartate (RGD)-bovine serum albumin (BSA)-polycaprolactone (PCL) (131I-RGD-BSA-PCL) in murine lung cancer models. MATERIALS AND METHODS: The target binding and cellular uptake of NCI-H460 lung cancer cells overexpressing integrin αvß3 were observed by confocal microscopy. Flow cytometry was used to assay apoptosis. The biologic effects of internal irradiation and the therapeutic efficacy of 131I-RGD-BSA-PCL were investigated in murine lung cancer models; tumor size, body weight, histopathologic findings, and SPECT/CT imaging findings were also monitored. RESULTS: In vitro uptake studies performed using confocal microscopy showed that, after 1 hour of incubation with RGD-BSA-PCL or BSA-PCL, visible fluorescence was present in the cells, and after 8 hours, the florescent signal did not disappear. The mean (± SE) tumor uptake level (i.e., the percentage of the injected dose per gram of tissue [% ID/g]) of 131I-labeled BSA-PCL (131I-BSA-PCL) at 24 and 72 hours after injection was 11.06% ± 2.15% ID/g and 3.83% ± 0.87% ID/g, respectively, which is significantly higher than the uptake levels noted for other organs (p < 0.05). The level of tumor uptake of 131I-RGD-BSA-PCL at 24 and 72 hours after injection was 39.49% ± 6.06% ID/g and 6.97% ± 1.43% ID/g, respectively, which is significantly higher than that of 131I-labeled liposome (p < 0.05). The decrease in body weight in the group treated with 131I-RGD-BSA-PCL was only 3.5% of the original body weight and was much lower than noted in the group receiving saline (i.e., 21.5% of original body weight). The median survival time for the therapeutic groups was prolonged to 27 days and 23 days after treatment with 131I-RGD-BSA-PCL and 131I-BSA-PCL, respectively. CONCLUSION: RGD-BSA-PCL has excellent cellular binding in vitro in a non-small cell lung cancer xenograft model. Furthermore, 131I-RGD-BSA-PCL was evaluated as an imaging agent and is an interesting candidate for targeting therapies in the non-small cell lung cancer xenograft model.


Assuntos
Radioisótopos do Iodo/farmacologia , Neoplasias Pulmonares/radioterapia , Terapia de Alvo Molecular/métodos , Oligopeptídeos/farmacologia , Poliésteres/farmacologia , Compostos Radiofarmacêuticos/farmacologia , Soroalbumina Bovina/farmacologia , Animais , Apoptose , Bovinos , Linhagem Celular Tumoral , Citometria de Fluxo , Xenoenxertos , Humanos , Radioisótopos do Iodo/farmacocinética , Lipossomos , Neoplasias Pulmonares/diagnóstico por imagem , Camundongos , Microscopia Confocal , Nanopartículas , Oligopeptídeos/farmacocinética , Poliésteres/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Aleatória , Soroalbumina Bovina/farmacocinética , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Nanomedicina Teranóstica
15.
Proc Natl Acad Sci U S A ; 111(28): 10037-44, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24961368

RESUMO

Phytochromes are dimeric proteins that function as red and far-red light sensors influencing nearly every phase of the plant life cycle. Of the three major phytochrome families found in flowering plants, phytochrome C (PHYC) is the least understood. In Arabidopsis and rice, PHYC is unstable and functionally inactive unless it heterodimerizes with another phytochrome. However, when expressed in an Arabidopsis phy-null mutant, wheat PHYC forms signaling active homodimers that translocate into the nucleus in red light to mediate photomorphogenic responses. Tetraploid wheat plants homozygous for loss-of-function mutations in all PHYC copies (phyC(AB)) flower on average 108 d later than wild-type plants under long days but only 19 d later under short days, indicating a strong interaction between PHYC and photoperiod. This interaction is further supported by the drastic down-regulation in the phyC(AB) mutant of the central photoperiod gene photoperiod 1 (PPD1) and its downstream target flowering locus T1, which are required for the promotion of flowering under long days. These results implicate light-dependent, PHYC-mediated activation of PPD1 expression in the acceleration of wheat flowering under inductive long days. Plants homozygous for the phyC(AB) mutations also show altered profiles of circadian clock and clock-output genes, which may also contribute to the observed differences in heading time. Our results highlight important differences in the photoperiod pathways of the temperate grasses with those of well-studied model plant species.


Assuntos
Núcleo Celular/metabolismo , Relógios Circadianos/fisiologia , Flores/metabolismo , Fotoperíodo , Fitocromo/metabolismo , Transdução de Sinais/fisiologia , Triticum/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Sequência de Bases , Núcleo Celular/genética , Flores/genética , Dados de Sequência Molecular , Mutação , Fitocromo/genética , Triticum/genética
16.
Plant J ; 84(1): 70-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26252567

RESUMO

The FLOWERING LOCUS T (FT) protein is a central component of a mobile flowering signal (florigen) that is transported from leaves to the shoot apical meristem (SAM). Two FT monomers and two DNA-binding bZIP transcription factors interact with a dimeric 14-3-3 protein bridge to form a hexameric protein complex. This complex, designated as the 'florigen activation complex' (FAC), plays a critical role in flowering. The wheat homologue of FT, designated FT1 (= VRN3), activates expression of VRN1 in the leaves and the SAM, promoting flowering under inductive long days. In this study, we show that FT1, other FT-like proteins, and different FD-like proteins, can interact with multiple wheat and barley 14-3-3 proteins. We also identify the critical amino acid residues in FT1 and FD-like proteins required for their interactions, and demonstrate that 14-3-3 proteins are necessary bridges to mediate the FT1-TaFDL2 interaction. Using in vivo bimolecular fluorescent complementation (BiFC) assays, we demonstrate that the interaction between FT1 and 14-3-3 occurs in the cytoplasm, and that this complex is then translocated to the nucleus, where it interacts with TaFDL2 to form a FAC. We also demonstrate that a FAC including FT1, TaFDL2 and Ta14-3-3C can bind to the VRN1 promoter in vitro. Finally, we show that relative transcript levels of FD-like and 14-3-3 genes vary among tissues and developmental stages. Since FD-like proteins determine the DNA specificity of the FACs, variation in FD-like gene expression can result in spatial and temporal modulation of the effects of mobile FT-like signals.


Assuntos
Florígeno/metabolismo , Hordeum/metabolismo , Proteínas de Plantas/metabolismo , Triticum/metabolismo , Regulação da Expressão Gênica de Plantas , Ligação Proteica
17.
Mol Cell Biochem ; 399(1-2): 279-89, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25410753

RESUMO

Malignant glioma can be treated with radioiodine following transfection with human sodium iodide symporter (hNIS) gene. Ad-Tp-E1A-Gp-NIS is engineered with human telomerase reverse transcriptase (hTERT) and glial fibrillary acidic protein (GFAP) promoters to express early region 1A (E1A) and hNIS genes, which may be useful in targeted gene therapy. The Ad-Tp-E1A-Gp-NIS was constructed and purified using the E1A and hNIS genes regulated by the hTERT and GFAP promoters, respectively. Glioma cells were infected by Ad-Tp-E1A-Gp-NIS. Selective replication ability of Ad-Tp-E1A-Gp-NIS was then evaluated by plaque forming assay, transgene expression by Western blot, (125)I-iodide uptake and efflux, clonogenicity following (131)I-iodide treatment in the tumor cells, and radioiodine therapy using nude mouse model. The Ad-Tp-E1A-Gp-NIS could selectively replicate; the hNIS gene was successfully expressed under the GFAP promoter. Western blot analyses using E1A- and hNIS-specific antibodies revealed two bands of approximately 40 and 70 kDa. In addition, the cells showed about 93.4 and 107.1 times higher (125)I uptake in U251 and U87 cells than in the control cells, respectively. Clonogenic assay indicated that >90% of cells transfected with Ad-Tp-E1A-Gp-NIS were killed. The Ad-Tp-E1A-Gp-NIS-transfected and 2 mCi (131)I-injected U87 xenograft nude mice survived the longest among the three groups. Ad-Tp-E1A-Gp-NIS has a good ability of selective replication and strong antitumor selectivity. An effective therapy of (131)I was achieved activity in malignant glioma cells after induction of tumor-specific iodide uptake activity by GFAP promoter-directed hNIS gene expression in vitro and in vivo.


Assuntos
Proteínas E1A de Adenovirus/genética , Proteína Glial Fibrilar Ácida/genética , Glioma/terapia , Radioisótopos do Iodo/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Simportadores/biossíntese , Telomerase/genética , Adenoviridae/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Terapia Combinada , Feminino , Terapia Genética , Glioma/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Regiões Promotoras Genéticas , Simportadores/genética , Carga Tumoral , Replicação Viral , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Oncol Lett ; 28(1): 297, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38751753

RESUMO

There is a correlation between tumors and immunity with the degree of immune cell infiltration in tumors being closely related to tumor growth and progression. Therefore, the present study identified immune-related prognostic genes and evaluated the immune infiltration level in lung adenocarcinoma (LUAD). This study performed Kyoto Encyclopedia of Genes and Genomes, Gene Ontology, and Gene Set Enrichment Analysis (GSEA) enrichment analyses on differential immune-associated genes. A risk model was created and validated using six immune-related prognostic genes. Reverse transcription-quantitative PCR was used to assess the prognostic gene expression in non-small cell lung cancer cells. Immune cell infiltration in LUAD was analyzed using the CIBERSORT method. Single sample GSEA was used to compare Tumor Immune Dysfunction and Exclusion (TIDE) scores between high and low-risk groups and to assess the activation of thirteen immune-related pathways. Multifactor Cox proportional hazards model analysis identified six prognostic risk genes (S100A16, FURIN, FGF2, LGR4, TNFRSF11A and VIPR1) to construct a risk model. The survival and receiver operating characteristic curves indicated that patients with higher risk scores had lower overall survival rates. The expression levels of prognostic genes S100A16, FURIN, LGR4, TNFRSF11A and VIPR1 were significantly increased in LUAD. B cells naive, plasma cells, T cells CD4 memory activated, T cells follicular helper, T cells regulatory, NK cells activated, macrophages M1, macrophages M2, and Dendritic cells resting cells showed elevated expression in LUAD. The prognostic genes were differentially associated with individual immune cells. Immune-related function scores, such as those for antigen presenting cell (APC) co-stimulation, APC co-inhibition, check-point, Cytolytic-activity, chemokine receptor, parainflammation, major histocompatibility complex-class-I, type-I-IFN-reponse and T-cell-co-inhibition, were higher in the high-risk group compared with the low-risk group. Furthermore, the TIDE score of the high-risk group was significantly lower than the low-risk group. This immune-related gene prognostic model has the potential to predict the prognosis of LUAD patients, supporting the development of a personalized clinical diagnosis and treatment plan.

19.
J Exp Bot ; 64(8): 2359-72, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23676884

RESUMO

Double fertilization of flowering plants depends on the targeted transportation of sperm to the embryo sac by the pollen tube. Currently, little is known about the underlying molecular mechanisms that regulate pollen germination and pollen tube growth in maize (Zea mays). Here, a maize pollen-predominant gene Zm908, with several putative short open reading frames (sORFs), was isolated and characterized. The longest ORF of Zm908 encodes a small protein of 97 amino acids. This was designated as Zm908p11 and is distributed throughout the maize pollen tube. Western blot detected the small peptide in mature pollen. Quantitative reverse transcription-PCR and northern blot analysis revealed that Zm908p11 was expressed predominantly in mature pollen grains. Ectopic overexpression of full-length Zm908 and Zm908p11 in tobacco resulted in defective pollen, while transgenic tobacco plants with a site-specific mutation or a frameshift mutation of Zm908p11 showed normal pollen development. Overexpression of Zm908p11 in maize decreased pollen germination efficiency. Maize pollen cDNA library screening and protein-protein interaction assays demonstrated that Zm908p11 interacts with maize profilin 1 (ZmPRO1). A microarray analysis identified 273 up-regulated and 203 down-regulated genes in the overexpressing transgenic Zm908p11 pollen. Taken together, these results indicate that Zm908 functions as Zm908p11, and binds to profilins as a novel ligand, with a required role during pollen tube growth in maize. Accordingly, a model is proposed for the role of Zm908p11 during pollen tube growth in maize.


Assuntos
Fases de Leitura Aberta/genética , Proteínas de Plantas/genética , Tubo Polínico/genética , Profilinas/fisiologia , Zea mays/genética , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Germinação/genética , Germinação/fisiologia , Dados de Sequência Molecular , Fases de Leitura Aberta/fisiologia , Proteínas de Plantas/análise , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Pólen/química , Tubo Polínico/química , Tubo Polínico/fisiologia , Profilinas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Nicotiana/genética , Zea mays/crescimento & desenvolvimento
20.
J Int Med Res ; 51(11): 3000605231187940, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37944187

RESUMO

OBJECTIVE: To identify the clinical features and prognostic factors for sublingual gland carcinoma. METHODS: This was a case-control study. Patients with surgically treated sublingual gland carcinoma were retrospectively included in the Surveillance, Epidemiology and End Results database and divided into adenoid cystic carcinoma (ACC) and non-ACC groups. Primary outcome variables were disease-specific survival (DSS) and overall survival (OS). Prognostic factors for each group were analyzed using Cox models. RESULTS: We included 251 patients (115 men and 136 women). Compared with the non-ACC group, the ACC group had a larger average tumor size and received more adjuvant radiotherapy. In patients with ACC, the pathologic grade had an independent impact on DSS and OS, and patients who were undergoing adjuvant chemotherapy had worse DSS than those who were not receiving chemotherapy. In the non-ACC group, pathologic grade IV, lymph node metastasis, and adjuvant chemotherapy were associated with poor DSS and OS, and tumor extension predicted worsening DSS. CONCLUSIONS: In sublingual gland carcinoma, the pathologic grade and adjuvant chemotherapy were the most important prognostic factors, whereas lymph node metastasis had a negative impact in non-ACC patients but not in ACC patients.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias das Glândulas Salivares , Masculino , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Metástase Linfática , Glândula Sublingual/patologia , Estudos de Casos e Controles , Neoplasias das Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/terapia , Carcinoma Adenoide Cístico/epidemiologia , Carcinoma Adenoide Cístico/terapia , Taxa de Sobrevida , Estadiamento de Neoplasias
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