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1.
Plant Cell ; 36(4): 812-828, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38231860

RESUMO

Single-cell and single-nucleus RNA-sequencing technologies capture the expression of plant genes at an unprecedented resolution. Therefore, these technologies are gaining traction in plant molecular and developmental biology for elucidating the transcriptional changes across cell types in a specific tissue or organ, upon treatments, in response to biotic and abiotic stresses, or between genotypes. Despite the rapidly accelerating use of these technologies, collective and standardized experimental and analytical procedures to support the acquisition of high-quality data sets are still missing. In this commentary, we discuss common challenges associated with the use of single-cell transcriptomics in plants and propose general guidelines to improve reproducibility, quality, comparability, and interpretation and to make the data readily available to the community in this fast-developing field of research.


Assuntos
Perfilação da Expressão Gênica , Plantas , Reprodutibilidade dos Testes , Plantas/genética , Estresse Fisiológico/genética , Armazenamento e Recuperação da Informação
2.
Plant Cell ; 33(2): 200-223, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33582756

RESUMO

Genome-wide gene expression maps with a high spatial resolution have substantially accelerated plant molecular science. However, the number of characterized tissues and growth stages is still small due to the limited accessibility of most tissues for protoplast isolation. Here, we provide gene expression profiles of the mature inflorescence stem of Arabidopsis thaliana covering a comprehensive set of distinct tissues. By combining fluorescence-activated nucleus sorting and laser-capture microdissection with next-generation RNA sequencing, we characterized the transcriptomes of xylem vessels, fibers, the proximal and distal cambium, phloem, phloem cap, pith, starch sheath, and epidermis cells. Our analyses classified more than 15,000 genes as being differentially expressed among different stem tissues and revealed known and novel tissue-specific cellular signatures. By determining overrepresented transcription factor binding regions in the promoters of differentially expressed genes, we identified candidate tissue-specific transcriptional regulators. Our datasets predict the expression profiles of an exceptional number of genes and allow hypotheses to be generated about the spatial organization of physiological processes. Moreover, we demonstrate that information about gene expression in a broad range of mature plant tissues can be established at high spatial resolution by nuclear mRNA profiling. Tissue-specific gene expression values can be accessed online at https://arabidopsis-stem.cos.uni-heidelberg.de/.


Assuntos
Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Inflorescência/genética , Caules de Planta/genética , Arabidopsis/fisiologia , Sítios de Ligação , Núcleo Celular/metabolismo , Bases de Dados Genéticas , Proteínas de Fluorescência Verde/metabolismo , Especificidade de Órgãos/genética , Floema/metabolismo , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA-Seq , Especificidade da Espécie , Fatores de Transcrição/metabolismo , Transgenes , Madeira/genética
3.
J Cell Sci ; 134(4)2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33468623

RESUMO

The molecular mechanisms by which cilia orientation is coordinated within and between multi-ciliated cells (MCCs) are not fully understood. In the mouse oviduct, MCCs exhibit a characteristic basal body (BB) orientation and microtubule gradient along the tissue axis. The intracellular polarities were moderately maintained in cells lacking CELSR1 (cadherin EGF LAG seven-pass G-type receptor 1), a planar cell polarity (PCP) factor involved in tissue polarity regulation, although the intercellular coordination of the polarities was disrupted. However, CAMSAP3 (calmodulin-regulated spectrin-associated protein 3), a microtubule minus-end regulator, was found to be critical for determining the intracellular BB orientation. CAMSAP3 localized to the base of cilia in a polarized manner, and its mutation led to the disruption of intracellular coordination of BB orientation, as well as the assembly of microtubules interconnecting BBs, without affecting PCP factor localization. Thus, both CELSR1 and CAMSAP3 are responsible for BB orientation but in distinct ways; their cooperation should therefore be critical for generating functional multi-ciliated tissues.


Assuntos
Caderinas , Cílios , Células Epiteliais , Proteínas Associadas aos Microtúbulos , Animais , Polaridade Celular , Feminino , Camundongos , Oviductos , Receptores Acoplados a Proteínas G
4.
Plant Physiol ; 188(1): 97-110, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34718781

RESUMO

Strigolactones (SLs) are a class of plant hormones that mediate biotic interactions and modulate developmental programs in response to endogenous and exogenous stimuli. However, a comprehensive view on the spatio-temporal pattern of SL signaling has not been established, and tools for a systematic in planta analysis do not exist. Here, we present Strigo-D2, a genetically encoded ratiometric SL signaling sensor that enables the examination of SL signaling distribution at cellular resolution and is capable of rapid response to altered SL levels in intact Arabidopsis (Arabidopsis thaliana) plants. By monitoring the abundance of a truncated and fluorescently labeled SUPPRESSOR OF MAX2 1-LIKE 6 (SMXL6) protein, a proteolytic target of the SL signaling machinery, we show that all cell types investigated have the capacity to respond to changes in SL levels but with very different dynamics. In particular, SL signaling is pronounced in vascular cells but low in guard cells and the meristematic region of the root. We also show that other hormones leave Strigo-D2 activity unchanged, indicating that initial SL signaling steps work in isolation from other hormonal signaling pathways. The specificity and spatio-temporal resolution of Strigo-D2 underline the value of the sensor for monitoring SL signaling in a broad range of biological contexts with highly instructive analytical depth.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Meristema/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Meristema/genética , Meristema/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/genética , Transdução de Sinais/genética
5.
Development ; 146(1)2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30626594

RESUMO

A reduced rate of stem cell division is considered a widespread feature which ensures the integrity of genetic information during somatic development of plants and animals. Radial growth of plant shoots and roots is a stem cell-driven process that is fundamental for the mechanical and physiological support of enlarging plant bodies. In most dicotyledonous species, the underlying stem cell niche, the cambium, generates xylem inwards and phloem outwards. Despite the importance and intriguing dynamics of the cambium, the functional characterization of its stem cells is hampered by the lack of experimental tools for accessing distinct cambium sub-domains. Here, we use the hypocotyl of Arabidopsis thaliana to map stem cell activity in the proliferating cambium. Through pulse labeling and genetically encoded lineage tracing, we find that a single bifacial stem cell generates both xylem and phloem cell lineages. This cell is characterized by a specific combination of PXY (TDR), SMXL5 and WOX4 gene activity and a high division rate in comparison with tissue-specific progenitors. Our analysis provides a cellular fate map of radial plant growth, and suggests that stem cell quiescence is not a general prerequisite for life-long tissue production.This article has an associated 'The people behind the papers' interview.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Câmbio/fisiologia , Floema/fisiologia , Células Vegetais/metabolismo , Desenvolvimento Vegetal/fisiologia , Células-Tronco/metabolismo , Xilema/fisiologia , Arabidopsis/citologia , Proteínas de Arabidopsis/biossíntese , Câmbio/citologia , Regulação da Expressão Gênica de Plantas/fisiologia , Hipocótilo/citologia , Hipocótilo/fisiologia , Floema/citologia , Raízes de Plantas/citologia , Raízes de Plantas/fisiologia , Células-Tronco/citologia , Xilema/citologia
6.
Plant J ; 102(5): 903-915, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31910293

RESUMO

As a pre-requisite for constant growth, plants produce vascular tissues at different sites within their post-embryonic body. Interestingly, the formation of vascular tissues during longitudinal and radial expansion of shoot and root axes differs fundamentally with respect to its anatomical configuration. This raises the question to which level regulatory mechanisms of vascular tissue formation are shared throughout plant development. Here, we show that, similar to primary phloem formation during longitudinal growth, the cambium-based formation of secondary phloem depends on the function of SUPPRESSOR OF MAX2 1-LIKE (SMXL) genes. In particular, local SMXL5 deficiency results in the absence of secondary phloem. Moreover, the additional disruption of SMXL4 activity increases tissue production in the cambium region without secondary phloem being formed. Using promoter-reporter lines, we observed that SMXL4 and SMXL5 activities are associated with different stages of secondary phloem formation in the Arabidopsis stem. Based on genome-wide transcriptional profiling and expression analyses of phloem-related markers, we concluded that early steps of phloem formation are impaired in smxl4;smxl5 double mutants and that the additional cambium-derived cells fail to establish phloem-related features. Our results showed that molecular mechanisms determining primary and secondary phloem formation share important properties, but differ slightly with SMXL5 playing a more dominant role in the formation of secondary phloem.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Floema/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células-Tronco/metabolismo
7.
Biochem Biophys Res Commun ; 521(3): 725-731, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706577

RESUMO

In this study, we aimed to test the effects of treadmill running on depression induced olfactory functions and OB neurogenesis in depression model. Depression model was created with chronic unpredictable mild stress (CUMS) and treadmill running was performed as the antidepressant treatment. Behavioral results showed that treadmill running not only attenuated the depression mood but also improved the olfactory discrimination and sensitivity in CUMS depression model. Immune-staining further indicates treadmill running promoted neurogenesis in hippocampal OB region. Moreover, treadmill running prevented the loss of DAergic neurons in glomerular layer of OB region, indicating the critical role of DAergic neuronal functions in regulating treadmill running mediated olfactory functions. In depression model, inhibiting DAergic neurons by intra-OB injection of 6-OHDA resulted in the compromised improving effects of treadmill running olfactory discrimination. In conclusion, treadmill running could attenuate depression associated olfactory deficits by promoting olfactory neurogenesis and improve DAergic neural functions.


Assuntos
Depressão/terapia , Terapia por Exercício , Neurogênese , Bulbo Olfatório/fisiopatologia , Animais , Depressão/fisiopatologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/patologia , Hipocampo/citologia , Hipocampo/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Bulbo Olfatório/citologia , Corrida
8.
EMBO Rep ; 19(7)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880710

RESUMO

The Wnt signaling pathway can be grouped into two classes, the ß-catenin-dependent and ß-catenin-independent pathways. Wnt5a signaling through a ß-catenin-independent pathway promotes microtubule (MT) remodeling during cell-substrate adhesion, cell migration, and planar cell polarity formation. Although Wnt5a signaling and MT remodeling are known to form an interdependent regulatory loop, the underlying mechanism remains unknown. Here we show that in HeLa cells, the paralogous MT-associated proteins Map7 and Map7D1 (Map7/7D1) form an interdependent regulatory loop with Disheveled, the critical signal transducer in Wnt signaling. Map7/7D1 bind to Disheveled, direct its cortical localization, and facilitate the cortical targeting of MT plus-ends in response to Wnt5a signaling. Wnt5a signaling also promotes Map7/7D1 movement toward MT plus-ends, and depletion of the Kinesin-1 member Kif5b abolishes the Map7/7D1 dynamics and Disheveled localization. Furthermore, Disheveled stabilizes Map7/7D1. Intriguingly, Map7/7D1 and its Drosophila ortholog, Ensconsin show planar-polarized distribution in both mouse and fly epithelia, and Ensconsin influences proper localization of Drosophila Disheveled in pupal wing cells. These results suggest that the role of Map7/7D1/Ensconsin in Disheveled localization is evolutionarily conserved.


Assuntos
Evolução Molecular , Proteínas Associadas aos Microtúbulos/genética , Proteína Wnt-5a/genética , Animais , Movimento Celular/genética , Polaridade Celular/genética , Proteínas Desgrenhadas/genética , Drosophila/genética , Células HeLa , Humanos , Cinesinas/genética , Camundongos , Ligação Proteica , Via de Sinalização Wnt/genética , beta Catenina/genética
9.
Development ; 141(23): 4558-68, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25406397

RESUMO

The oviduct is an important organ in reproduction where fertilization occurs, and through which the fertilized eggs are carried to the uterus in mammals. This organ is highly polarized, where the epithelium forms longitudinal folds along the ovary-uterus axis, and the epithelial multicilia beat towards the uterus to transport the ovulated ova. Here, we analyzed the postnatal development of mouse oviduct and report that multilevel polarities of the oviduct are regulated by a planar cell polarity (PCP) gene, Celsr1. In the epithelium, Celsr1 is concentrated in the specific cellular boundaries perpendicular to the ovary-uterus axis from postnatal day 2. We found a new feature of cellular polarity in the oviduct - the apical surface of epithelial cells is elongated along the ovary-uterus axis. In Celsr1-deficient mice, the ciliary motion is not orchestrated along the ovary-uterus axis and the transport ability of beating cilia is impaired. Epithelial cells show less elongation and randomized orientation, and epithelial folds show randomized directionality and ectopic branches in the mutant. Our mosaic analysis suggests that the geometry of epithelial cells is primarily regulated by Celsr1 and as a consequence the epithelial folds are aligned. Taken together, we reveal the characteristics of the multilevel polarity formation processes in the mouse oviduct epithelium and suggest a novel function of the PCP pathway for proper tissue morphogenesis.


Assuntos
Polaridade Celular/fisiologia , Células Epiteliais/fisiologia , Organogênese/fisiologia , Oviductos/embriologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Bromodesoxiuridina , Polaridade Celular/genética , Forma Celular/fisiologia , Cílios/fisiologia , Primers do DNA/genética , Feminino , Fluorescência , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microesferas , Oviductos/ultraestrutura , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Biophys J ; 111(3): 650-665, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27508448

RESUMO

Epithelia exhibit various three-dimensional morphologies linked to organ function in animals. However, the mechanisms of three-dimensional morphogenesis remain elusive. The luminal epithelium of the mouse oviduct forms well-aligned straight folds along the longitudinal direction of the tubes. Disruption of the Celsr1 gene, a planar cell polarity-related gene, causes ectopically branched folds. Here, we evaluated the mechanical contributions of the epithelium to the fold pattern formation. In the mutant oviduct, the epithelium was more intricate along the longitudinal direction than in the wild-type, suggesting a higher ratio of the longitudinal length of the epithelial layer to that of the surrounding smooth muscle (SM) layer (L-Epi/SM ratio). Our mathematical modeling and computational simulations suggested that the L-Epi/SM ratio could explain the differences in fold branching between the two genotypes. Longitudinal epithelial tensions were increased in well-aligned folds compared with those in disorganized folds both in the simulations and in experimental estimations. Artificially increasing the epithelial tensions suppressed the branching in simulations, suggesting that the epithelial tensions can regulate fold patterning. The epithelial tensions could be explained by the combination of line tensions along the epithelial cell-cell boundaries with the polarized cell arrays observed in vivo. These results suggest that the fold pattern is associated with the polarized cell array through the longitudinal epithelial tension. Further simulations indicated that the L-Epi/SM ratio could contribute to fold pattern diversity, suggesting that the L-Epi/SM ratio is a critical parameter in the fold patterning in tubular organs.


Assuntos
Epitélio/metabolismo , Tubas Uterinas/citologia , Tubas Uterinas/crescimento & desenvolvimento , Fenômenos Mecânicos , Morfogênese , Animais , Fenômenos Biomecânicos , Feminino , Camundongos , Modelos Biológicos , Miócitos de Músculo Liso/citologia , Estresse Mecânico
11.
Dev Dyn ; 243(6): 791-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24403181

RESUMO

BACKGROUND: Planar cell polarity (PCP) originally referred to the coordination of global organ axes and individual cell polarity within the plane of the epithelium. More recently, it has been accepted that pertinent PCP regulators play essential roles not only in epithelial sheets, but also in various rearranging cells. RESULTS: We identified pepsinogen-like (pcl) as a new planar polarity gene, using Drosophila wing epidermis as a model. Pcl protein is predicted to belong to a family of aspartic proteases. When pcl mutant clones were observed in pupal wings, PCP was disturbed in both mutant and wild-type cells that were juxtaposed to the clone border. We examined levels of known PCP proteins in wing imaginal discs. The amount of the seven-pass transmembrane cadherin Flamingo (Fmi), one of the PCP "core group" members, was significantly decreased in mutant clones, whereas neither the amount of nor the polarized localization of Dachsous (Ds) at cell boundaries was affected. In addition to the PCP phenotype, the pcl mutation caused loss of wing margins. Intriguingly, this was most likely due to a dramatic decrease in the level of Wingless (Wg) protein, but not due to a decrease in the level of wg transcripts. CONCLUSIONS: Our results raise the possibility that Pcl regulates Wg expression post-transcriptionally, and PCP, by proteolytic cleavages.


Assuntos
Caderinas/metabolismo , Proteínas de Drosophila/biossíntese , Proteínas de Drosophila/metabolismo , Embrião não Mamífero/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Discos Imaginais/embriologia , Proteólise , Proteína Wnt1/biossíntese , Animais , Drosophila melanogaster , Embrião não Mamífero/citologia , Discos Imaginais/citologia
12.
Methods Mol Biol ; 2722: 67-78, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37897600

RESUMO

Nuclei contain essential information for cell states, including chromatin and RNA profiles - features which are nowadays accessible using high-throughput sequencing applications. Here, we describe analytical pipelines including nucleus isolation from differentiated xylem tissues by fluorescence-activated nucleus sorting (FANS), as well as subsequent SMART-seq2-based transcriptome profiling and assay for transposase-accessible chromatin (ATAC)-seq-based chromatin analysis. Combined with tissue-specific expression of nuclear fluorescent reporters, these pipelines allow obtaining tissue-specific data on gene expression and on chromatin structure and are applicable for a large spectrum of cell types, tissues, and organs. Considering, however, the extreme degree of differentiation found in xylem cells with programmed cell death happening during vessel element formation and their role as a long-term depository for atmospheric CO2 in the form of wood, xylem cells represent intriguing and relevant objects for large-scale profilings of their cellular signatures.


Assuntos
Núcleo Celular , Cromatina , Cromatina/genética , Cromatina/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Transcriptoma , Sequenciamento de Nucleotídeos em Larga Escala , Perfilação da Expressão Gênica , Xilema , Análise de Sequência de DNA
13.
Science ; 379(6627): 62-65, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36603081

RESUMO

In this study, we examined China's Young Thousand Talents (YTT) program and evaluated its effectiveness in recruiting elite expatriate scientists and in nurturing the returnee scientists' productivity. We find that YTT scientists are generally of high caliber in research but, as a group, fall below the top category in pre-return productivity. We further find that YTT scientists are associated with a post-return publication gain across journal-quality tiers. However, this gain mainly takes place in last-authored publications and for high-caliber (albeit not top-caliber) recruits and can be explained by YTT scientists' access to greater funding and larger research teams. This paper has policy implications for the mobility of scientific talent, especially as early-career scientists face growing challenges in accessing research funding in the United States and European Union.

14.
Nat Commun ; 14(1): 2128, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059727

RESUMO

Spatial specificity of cell fate decisions is central for organismal development. The phloem tissue mediates long-distance transport of energy metabolites along plant bodies and is characterized by an exceptional degree of cellular specialization. How a phloem-specific developmental program is implemented is, however, unknown. Here we reveal that the ubiquitously expressed PHD-finger protein OBE3 forms a central module with the phloem-specific SMXL5 protein for establishing the phloem developmental program in Arabidopsis thaliana. By protein interaction studies and phloem-specific ATAC-seq analyses, we show that OBE3 and SMXL5 proteins form a complex in nuclei of phloem stem cells where they promote a phloem-specific chromatin profile. This profile allows expression of OPS, BRX, BAM3, and CVP2 genes acting as mediators of phloem differentiation. Our findings demonstrate that OBE3/SMXL5 protein complexes establish nuclear features essential for determining phloem cell fate and highlight how a combination of ubiquitous and local regulators generate specificity of developmental decisions in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Floema/metabolismo , Arabidopsis/metabolismo , Proteínas de Membrana/metabolismo , Diferenciação Celular , Regulação da Expressão Gênica de Plantas
15.
Genes Cells ; 16(3): 282-90, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21294816

RESUMO

The oviduct is important in reproduction where fertilization occurs, and the fertilized eggs are conveyed to the uterus. Multi-ciliated cells of the oviductal epithelium and muscle contractions are believed to generate this unidirectional flow. Although there are many studies in human oviducts, there are few reports on mouse oviductal ciliary movements where we can dissect underlying genetic programs. To study ciliary movements in the mouse oviduct, we exposed the ovary-side of the oviduct (infundibulum) longitudinally and recorded the ciliary beatings in a hanging drop preparation. We calculated the ciliary beat frequency (CBF) by automated image analysis and found that the average CBF was 10.9 ± 3.3 and 8.5 ± 2.5 Hz (±standard deviation) during the diestrus and estrus stages, respectively. Mapping of the CBF to multiple locations in the epithelium showed that the cilia beat regularly at a local level, but have a range of frequencies within the entire plane. We also observed ova with cumulus cells were transported to the uterus side by the opened oviduct at the diestrus and estrus stages. These results suggest that the ciliated cells of the infundibulum can generate unidirectional flows and are able to deliver ova by their ciliary activities despite their discordance in beating periodicity.


Assuntos
Cílios/fisiologia , Camundongos/fisiologia , Oviductos/fisiologia , Transporte do Óvulo , Animais , Epitélio/fisiologia , Feminino , Técnicas In Vitro , Oviductos/citologia
16.
Front Plant Sci ; 13: 864422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548289

RESUMO

Precise coordination of cell fate decisions is a hallmark of multicellular organisms. Especially in tissues with non-stereotypic anatomies, dynamic communication between developing cells is vital for ensuring functional tissue organization. Radial plant growth is driven by a plant stem cell niche known as vascular cambium, usually strictly producing secondary xylem (wood) inward and secondary phloem (bast) outward, two important structures serving as much-needed CO2 depositories and building materials. Because of its bidirectional nature and its developmental plasticity, the vascular cambium serves as an instructive paradigm for investigating principles of tissue patterning. Although genes and hormones involved in xylem and phloem formation have been identified, we have a yet incomplete picture of the initial steps of cell fate transitions of stem cell daughters into xylem and phloem progenitors. In this mini-review perspective, we describe two possible scenarios of cell fate decisions based on the current knowledge about gene regulatory networks and how cellular environments are established. In addition, we point out further possible research directions.

17.
Curr Biol ; 32(8): 1764-1775.e3, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35294866

RESUMO

Plant secondary growth, which is the basis of wood formation, includes the production of secondary xylem, which is derived from meristematic cambium cells embedded in vascular tissue. Here, we identified an important role for the Arabidopsis thaliana (Arabidopsis) AT-HOOK MOTIF CONTAINING NUCLEAR LOCALIZED 15 (AHL15) transcriptional regulator in controlling vascular cambium activity. The limited secondary xylem development in inflorescence stems of herbaceous Arabidopsis plants was significantly reduced in ahl15 loss-of-function mutants, whereas constitutive or vascular meristem-specific AHL15 overexpression produced woody inflorescence stems. AHL15 was required for enhanced secondary xylem formation in the woody suppressor of overexpression of constans 1 (soc1) fruitfull (ful) double loss-of-function mutant. Moreover, we found that AHL15 induces vascular cambium activity downstream of the repressing SOC1 and FUL transcription factors, most likely similar to how it enhances lateral branching by promoting biosynthesis of the hormone cytokinin. Our results uncover a novel pathway driving cambium development, in which AHL15 expression levels act in parallel to and are dependent on the well-established TDIF-PXY-WOX pathway to differentiate between herbaceous and woody stem growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Câmbio/genética , Regulação da Expressão Gênica de Plantas , Meristema/metabolismo , Xilema/metabolismo
18.
Biophys Physicobiol ; 16: 89-107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30923666

RESUMO

Organs and tissues in multi-cellular organisms exhibit various morphologies. Tubular organs have multi-scale morphological features which are closely related to their functions. Here we discuss morphogenesis and the mechanical functions of the vertebrate oviduct in the female reproductive tract, also known as the fallopian tube. The oviduct functions to convey eggs from the ovary to the uterus. In the luminal side of the oviduct, the epithelium forms multiple folds (or ridges) well-aligned along the longitudinal direction of the tube. In the epithelial cells, cilia are formed orienting toward the downstream of the oviduct. The cilia and the folds are supposed to be involved in egg transportation. Planar cell polarity (PCP) is developed in the epithelium, and the disruption of the Celsr1 gene, a PCP related-gene, causes randomization of both cilia and fold orientations, discontinuity of the tube, inefficient egg transportation, and infertility. In this review article, we briefly introduce various biophysical and biomechanical issues in the oviduct, including physical mechanisms of formation of PCP and organized cilia orientation, epithelial cell shape regulation, fold pattern formation generated by mechanical buckling, tubulogenesis, and egg transportation regulated by fluid flow. We also mention about possible roles of the oviducts in egg shape formation and embryogenesis, sinuous patterns of tubes, and fold and tube patterns observed in other tubular organs such as the gut, airways, etc.

19.
Rev. bras. med. esporte ; 28(5): 479-482, Set.-Oct. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1376703

RESUMO

ABSTRACT Introduction: Soccer is one of the sports with the highest incidence of injuries, generated both by the high performance required on the field and by physical conflicts between players. A fast rehabilitation is essential for the player's performance. It has been empirically observed that an early recovery in patients' rehabilitation is associated with physical training compared to players who received only the traditional rehabilitation. Objective: Verify the physical training influence on rehabilitation sports injuries in male soccer players. Method: 180 cases of male adolescents with sports injuries admitted to a Taiyuan hospital were selected. A division into two groups was randomly computerized to avoid statistical differences in the intensity of the injuries. The control group (14.3±2.45 years old) was treated with the standard protocol, while the experimental group (15.3±2.95 years old) received an intervention with physical training. Interviews and questionnaires were conducted involving analysis of time and severity of the injury, laterality, and location. The control group received treatment based on this information. The recovery rate and intervention satisfaction rate were collected. SPSS22.0 Statistical Software was used for student's t-test and chi-square test. Results: Treatment efficiency was 82 (91.11%) in the control group versus 88 (97.78%) in the experimental group. The degree of dissatisfaction was 1 (2.11%) versus 8 (10%). The perceived overall satisfaction was 80 (89%) versus 87 (96.67%), (p <0.05). Conclusion: Rehabilitation associated with physical training intervention improved satisfaction and treatment efficiency. Evidence Level II; Therapeutic Studies - Investigating the results.


RESUMO Introdução: O futebol é um dos esportes com maior incidência de lesões, geradas tanto pelo alto desempenho exigido em campo quanto por conflitos físicos entre jogadores. Uma breve reabilitação é essencial para o rendimento do jogador. Percebe-se, de forma empírica, uma alta precoce em pacientes submetidos ao treinamento físico associado, quando comparados aos jogadores destinados à reabilitação tradicional. Objetivo: Verificar a influência do treinamento físico na reabilitação de lesões esportivas nos jogadores de futebol masculino. Método: Foram selecionados 180 casos de adolescentes masculinos com lesões esportivas internados neste hospital. A divisão em dois grupos foi efetuada aleatoriamente de forma computadorizada afim de evitar diferenças estatísticas na intensidade das lesões. O grupo controle (idade média 14,3±2,45 anos) foi tratado com o protocolo padrão enquanto ao experimental (idade média 15,3±2,95 anos) foi adicionada uma intervenção com treinamento físico. Foram efetuadas entrevistas e questionários envolvendo análise de tempo e gravidade da lesão, lateralidade e localização. O grupo controle recebeu o tratamento norteado nessas informações. Foram coletados a taxa de recuperação e a taxa de satisfação de intervenção. Foi utilizado o Software Estatístico SPSS22.0 para os testes t de student e qui-quadrado. Resultados: A eficiência do tratamento foi de 82 (91,11%) no grupo controle contra 88 (97,78%) no grupo experimental. O grau de insatisfação foi de 1 (2,11%) contra 8 (10%). A percepção de satisfação total foi de 80 (89%) contra 87 (96,67%), (p <0,05). Conclusão: A reabilitação associada à intervenção de treinamento físico demonstrou melhorar a taxa de satisfação e a eficiência do tratamento. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.


RESUMEN Introducción: El fútbol es uno de los deportes con mayor incidencia de lesiones, generadas tanto por el alto rendimiento requerido en el campo como por los conflictos físicos entre los jugadores. Una pronta rehabilitación es esencial para el rendimiento del jugador. Se ha observado empíricamente que una recuperación temprana en la rehabilitación de los pacientes se asocia con la adición del entrenamiento físico en comparación con los jugadores que sólo recibieron la rehabilitación tradicional. Objetivo: Verificar la influencia del entrenamiento físico en la rehabilitación de lesiones deportivas en jugadores de fútbol masculinos. Métodos: Se seleccionaron 180 casos de adolescentes masculinos con lesiones deportivas ingresados en un hospital de Taiyuan. Se realizó una división en dos grupos de forma aleatoria para evitar diferencias estadísticas en la intensidad de las lesiones. El grupo de control (14,3±2,45 años) fue tratado con el protocolo estándar, mientras que el grupo experimental (15,3±2,95 años) recibió una intervención con entrenamiento físico. Se realizaron entrevistas y cuestionarios que incluían el análisis del tiempo y la gravedad de la lesión, la lateralidad y la localización. El grupo de control recibió un tratamiento basado en esta información. Se recogió el índice de recuperación y el índice de satisfacción de la intervención. Se utilizó el software estadístico SPSS22.0 para la prueba t de student y la prueba chi-cuadrado. Resultados: La eficacia del tratamiento fue de 82 (91,11%) en el grupo de control frente a 88 (97,78%) en el grupo experimental. El grado de insatisfacción fue de 1 (2,11%) frente a 8 (10%). La satisfacción global percibida fue de 80 (89%) frente a 87 (96,67%), (p <0,05). Conclusión: La rehabilitación asociada a la intervención de entrenamiento físico mejoró la satisfacción y la eficacia del tratamiento. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.

20.
PLoS One ; 12(9): e0184977, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28934277

RESUMO

Humanities and Social Sciences (HSS) increasingly absorb knowledge from Hard Sciences, i.e., Science, Technology, Agriculture and Medicine (STAM), as testified by a growing number of citations. However, whether citing more Hard Sciences brings more citations to HSS remains to be investigated. Based on China's HSS articles indexed by the Web of Science during 1998-2014, this paper estimated two-way fixed effects negative binomial models, with journal effects and year effects. Findings include: (1) An inverse U-shaped curve was observed between the percentage of STAM references to the HSS articles and the number of citations they received; (2) STAM contributed increasing knowledge to China's HSS, while Science and Technology knowledge contributed more citations to HSS articles. It is recommended that research policy should be adjusted to encourage HSS researchers to adequately integrate STAM knowledge when conducting interdisciplinary research, as over-cited STAM knowledge may jeopardize the readability of HSS articles.


Assuntos
Pesquisa Biomédica , Ciências Humanas , Ciência , Ciências Sociais , Tecnologia , Bibliometria , Humanos , Estudos Interdisciplinares
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