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1.
Mol Cell Proteomics ; 23(3): 100729, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309569

RESUMO

Diagnosing, predicting disease outcome, and identifying effective treatment targets for virus-related cancers are lacking. Protein biomarkers have the potential to bridge the gap between prevention and treatment for these types of cancers. While it has been shown that certain antibodies against EBV proteins could be used to detect nasopharyngeal carcinoma (NPC), antibodies targeting are solely a tiny part of the about 80 proteins expressed by the EBV genome. Furthermore, it remains unclear what role other viruses play in NPC since many diseases are the result of multiple viral infections. For the first time, this study measured both IgA and IgG antibody responses against 646 viral proteins from 23 viruses in patients with NPC and control subjects using nucleic acid programmable protein arrays. Candidate seromarkers were then validated by ELISA using 1665 serum samples from three clinical cohorts. We demonstrated that the levels of five candidate seromarkers (EBV-BLLF3-IgA, EBV-BLRF2-IgA, EBV-BLRF2-IgG, EBV-BDLF1-IgA, EBV-BDLF1-IgG) in NPC patients were significantly elevated than controls. Additional examination revealed that NPC could be successfully diagnosed by combining the clinical biomarker EBNA1-IgA with the five anti-EBV antibodies. The sensitivity of the six-antibody signature at 95% specificity to diagnose NPC was comparable to the current clinically-approved biomarker combination, VCA-IgA, and EBNA1-IgA. However, the recombinant antigens of the five antibodies are easier to produce and standardize compared to the native viral VCA proteins. This suggests the potential replacement of the traditional VCA-IgA assay with the 5-antibodies combination to screen and diagnose NPC. Additionally, we investigated the prognostic significance of these seromarkers titers in NPC. We showed that NPC patients with elevated BLLF3-IgA and BDLF1-IgA titers in their serum exhibited significantly poorer disease-free survival, suggesting the potential of these two seromarkers as prognostic indicators of NPC. These findings will help develop serological tests to detect and treat NPC in the future.


Assuntos
Neoplasias Nasofaríngeas , Proteoma , Humanos , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Herpesvirus Humano 4/genética , Proteínas do Capsídeo , Antígenos Virais , Biomarcadores , Imunoglobulina G , Imunoglobulina A
2.
Biochem Biophys Res Commun ; 702: 149652, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38341922

RESUMO

Prostatic acid phosphatase (PAP) is a glycoprotein that plays a crucial role in the hydrolysis of phosphate ester present in prostatic exudates. It is a well-established indicator for prostate cancer due to its elevated serum levels in disease progression. Despite its abundance in semen, PAP's influence on male fertility has not been extensively studied. In our study, we report a significantly optimized method for purifying human endogenous PAP, achieving remarkably high efficiency and active protein recovery rate. This achievement allowed us to better analyze and understand the PAP protein. We determined the cryo-electron microscopic (Cryo-EM) structure of prostatic acid phosphatase in its physiological state for the first time. Our structural and gel filtration analysis confirmed the formation of a tight homodimer structure of human PAP. This functional homodimer displayed an elongated conformation in the cryo-EM structure compared to the previously reported crystal structure. Additionally, there was a notable 5-degree rotation in the angle between the α domain and α/ß domain of each monomer. Through structural analysis, we revealed three potential glycosylation sites: Asn94, Asn220, and Asn333. These sites contained varying numbers and forms of glycosyl units, suggesting sugar moieties influence PAP function. Furthermore, we found that the active sites of PAP, His44 and Asp290, are located between the two protein domains. Overall, our study not only provide an optimized approach for PAP purification, but also offer crucial insights into its structural characteristics. These findings lay the groundwork for further investigations into the physiological function and potential therapeutic applications of this important protein.


Assuntos
Neoplasias da Próstata , Sêmen , Humanos , Masculino , Sêmen/química , Sêmen/metabolismo , Microscopia Crioeletrônica , Próstata/metabolismo , Fosfatase Ácida/metabolismo
3.
J Transl Med ; 22(1): 690, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075486

RESUMO

BACKGROUND: To provide a preoperative prediction model for lymph node metastasis in pancreatic cancer patients and provide molecular information of key radiomic features. METHODS: Two cohorts comprising 151 and 54 pancreatic cancer patients were included in the analysis. Radiomic features from the tumor region of interests were extracted by using PyRadiomics software. We used a framework that incorporated 10 machine learning algorithms and generated 77 combinations to construct radiomics-based models for lymph node metastasis prediction. Weighted gene coexpression network analysis (WGCNA) was subsequently performed to determine the relationships between gene expression levels and radiomic features. Molecular pathways enrichment analysis was performed to uncover the underlying molecular features. RESULTS: Patients in the in-house cohort (mean age, 61.3 years ± 9.6 [SD]; 91 men [60%]) were separated into training (n = 105, 70%) and validation (n = 46, 30%) cohorts. A total of 1,239 features were extracted and subjected to machine learning algorithms. The 77 radiomic models showed moderate performance for predicting lymph node metastasis, and the combination of the StepGBM and Enet algorithms had the best performance in the training (AUC = 0.84, 95% CI = 0.77-0.91) and validation (AUC = 0.85, 95% CI = 0.73-0.98) cohorts. We determined that 15 features were core variables for lymph node metastasis. Proliferation-related processes may respond to the main molecular alterations underlying these features. CONCLUSIONS: Machine learning-based radiomics could predict the status of lymph node metastasis in pancreatic cancer, which is associated with proliferation-related alterations.


Assuntos
Metástase Linfática , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Pessoa de Meia-Idade , Masculino , Metástase Linfática/patologia , Feminino , Genômica , Aprendizado de Máquina , Anotação de Sequência Molecular , Regulação Neoplásica da Expressão Gênica , Estudos de Coortes , Idoso , Algoritmos , Redes Reguladoras de Genes , Curva ROC , Reprodutibilidade dos Testes , Radiômica
4.
Biochem Genet ; 62(2): 1040-1054, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37528284

RESUMO

Anoectochilus roxburghii (Wall.) Lindl is a perennial herb of the Orchidaceae family; a yellow-green mutant and a yellow mutant were obtained from the wild type, thereby providing good material for the study of leaf color variation. Pigment content analysis revealed that chlorophyll, carotenoids, and anthocyanin were lower in the yellow-green and yellow mutants than in the wild type. Transcriptome analysis of the yellow mutant and wild type revealed that 78,712 unigenes were obtained, and 599 differentially expressed genes (120 upregulated and 479 downregulated) were identified. Using the Kyoto Encyclopedia of Genes and Genomes pathway analysis, candidate genes involved in the anthocyanin biosynthetic pathway (five unigenes) and the chlorophyll metabolic pathway (two unigenes) were identified. Meanwhile, the low expression of the chlorophyll and anthocyanin biosynthetic genes resulted in the absence of chlorophylls and anthocyanins in the yellow mutant. This study provides a basis for similar research in other closely related species.

5.
Plant Biotechnol J ; 21(4): 680-697, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36221230

RESUMO

Global food security is one of the utmost essential challenges in the 21st century in providing enough food for the growing population while coping with the already stressed environment. High temperature (HT) is one of the main factors affecting plant growth, development and reproduction and causes male sterility in plants. In male reproductive tissues, metabolic changes induced by HT involve carbohydrates, lipids, hormones, epigenetics and reactive oxygen species, leading to male sterility and ultimately reducing yield. Understanding the mechanism and genes involved in these pathways during the HT stress response will provide a new path to improve crops by using molecular breeding and biotechnological approaches. Moreover, this review provides insight into male sterility and integrates this with suggested strategies to enhance crop tolerance under HT stress conditions at the reproductive stage.


Assuntos
Temperatura Alta , Infertilidade Masculina , Masculino , Humanos , Temperatura , Produtos Agrícolas/genética
6.
Plant Physiol ; 189(4): 2091-2109, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522025

RESUMO

High temperature (HT) causes male sterility and decreases crop yields. Our previous works have demonstrated that sugar and auxin signaling pathways, Gossypium hirsutum Casein kinase I (GhCKI), and DNA methylation are all involved in HT-induced male sterility in cotton. However, the signaling mechanisms leading to distinct GhCKI expression patterns induced by HT between HT-tolerant and HT-sensitive cotton anthers remain largely unknown. Here, we identified a GhCKI promoter (ProGhCKI) region that functions in response to HT in anthers and found the transcription factor GhMYB4 binds to this region to act as an upstream positive regulator of GhCKI. In the tapetum of early-stage cotton anthers, upregulated expression of GhMYB4 under HT and overexpressed GhMYB4 under normal temperature both led to severe male sterility phenotypes, coupled with enhanced expression of GhCKI. We also found that GhMYB4 interacts with GhMYB66 to form a heterodimer to enhance its binding to ProGhCKI. However, GhMYB66 showed an expression pattern similar to GhMYB4 under HT but did not directly bind to ProGhCKI. Furthermore, HT reduced siRNA-mediated CHH DNA methylations in the GhMYB4 promoter, which enhanced the expression of GhMYB4 in tetrad stage anthers and promoted the formation of the GhMYB4/GhMYB66 heterodimer, which in turn elevated the transcription of GhCKI in the tapetum, leading to male sterility. Overall, we shed light on the GhMYB66-GhMYB4-GhCKI regulatory pathway in response to HT in cotton anthers.


Assuntos
Gossypium , Infertilidade Masculina , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/metabolismo , Temperatura Alta , Humanos , Masculino , Temperatura
7.
Angew Chem Int Ed Engl ; 62(8): e202215616, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36573021

RESUMO

Herein, an I2 -catalyzed unprecedented cycloisomerization of ynamides is developed, furnishing various functionalized bis(indole) derivatives in generally good to excellent yields with wide substrate scope and excellent atom-economy. This protocol not only represents the first molecular-iodine-catalyzed tandem complex alkyne cycloisomerizations, but also constitutes the first chemoselective cycloisomerization of tryptamine-ynamides involving distinctively different C(sp3 )-C(sp3 ) bond cleavage and rearrangement. Moreover, chiral tetrahydropyridine frameworks containing two stereocenters are obtained with moderate to excellent diastereoselectivities and excellent enantioselectivities. Meanwhile, cycloisomerization and aromatization of ynamides produce pyrrolyl indoles with high efficiency enabled by I2 . Additionally, control experiments and theoretical calculations reveal that this reaction probably undergoes a tandem 5-exo-dig cyclization/rearrangement process.

8.
Plant Biotechnol J ; 20(6): 1054-1068, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35114063

RESUMO

The pollen wall exine provides a protective layer for the male gametophyte and is largely composed of sporopollenin, which comprises fatty acid derivatives and phenolics. However, the biochemical nature of the external exine is poorly understood. Here, we show that the male sterile line 1355A of cotton mutated in NO SPINE POLLEN (GhNSP) leads to defective exine formation. The GhNSP locus was identified through map-based cloning and confirmed by genetic analysis (co-segregation test and allele prediction using the CRISPR/Cas9 system). In situ hybridization showed that GhNSP is highly expressed in tapetum. GhNSP encodes a polygalacturonase protein homologous to AtQRT3, which suggests a function for polygalacturonase in pollen exine formation. These results indicate that GhNSP is functionally different from AtQRT3, the latter has the function of microspore separation. Biochemical analysis showed that the percentage of de-esterified pectin was significantly increased in the 1355A anthers at developmental stage 8. Furthermore, immunofluorescence studies using antibodies to the de-esterified and esterified homogalacturonan (JIM5 and JIM7) showed that the Ghnsp mutant exhibits abundant of de-esterified homogalacturonan in the tapetum and exine, coupled with defective exine formation. The characterization of GhNSP provides new understanding of the role of polygalacturonase and de-esterified homogalacturonan in pollen exine formation.


Assuntos
Regulação da Expressão Gênica de Plantas , Poligalacturonase , Fertilidade , Pectinas/metabolismo , Pólen/genética , Pólen/metabolismo , Poligalacturonase/genética , Poligalacturonase/metabolismo
9.
Scand J Gastroenterol ; 57(3): 352-358, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34779685

RESUMO

OBJECTIVES: To explore and establish a reliable and noninvasive ultrasound model for predicting the biological risk of gastrointestinal stromal tumors (GISTs). MATERIALS AND METHODS: We retrospectively reviewed 266 patients with pathologically-confirmed GISTs and 191 patients were included. Data on patient sex, age, tumor location, biological risk classification, internal echo, echo homogeneity, boundary, shape, blood flow signals, presence of necrotic cystic degeneration, long diameter, and short/long (S/L) diameter ratio were collected. All patients were divided into low-, moderate-, and high-risk groups according to the modified NIH classification criteria. All indicators were analyzed by univariate analysis. The indicators with inter-group differences were used to establish regression and decision tree models to predict the biological risk of GISTs. RESULTS: There were statistically significant differences in long diameter, S/L ratio, internal echo level, echo homogeneity, boundary, shape, necrotic cystic degeneration, and blood flow signals among the low-, moderate-, and high-risk groups (all p < .05). The logistic regression model based on the echo homogeneity, shape, necrotic cystic degeneration and blood flow signals had an accuracy rate of 76.96% for predicting the biological risk, which was higher than the 72.77% of the decision tree model (based on the long diameter, the location of tumor origin, echo homogeneity, shape, and internal echo) (p = .008). In the low-risk and high-risk groups, the predicting accuracy rates of the regression model reached 87.34 and 81.82%, respectively. CONCLUSIONS: Transabdominal ultrasound is highly valuable in predicting the biological risk of GISTs. The logistic regression model has greater predictive value than the decision tree model.


Assuntos
Tumores do Estroma Gastrointestinal , Endossonografia , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/patologia , Humanos , Modelos Logísticos , Estudos Retrospectivos , Ultrassonografia
10.
Int J Med Sci ; 19(10): 1586-1595, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185335

RESUMO

Background: Resveratrol, a natural antioxidant polyphenol, has the functions of anti-inflammation, anti-cancer, liver protection and cardioprotection. Microorganism biotransformation-produced resveratrol (MBR) product shows higher purity than the natural source of resveratrol and costs less than the chemically synthesized resveratrol. The aim of the present study was to investigate the protective effects of MBR in hamsters treated with a high-fat diet (HFD). Methods: MBR was obtained by the fermentative process of piceid. Hamsters were randomly divided into four groups: HFD plus oral administration of MBR 0 (C), 5 (L), 20 (M) or 50 mg/kg (H), respectively. After six-week of treatment, hamsters were sacrificed, and tissues were collected for further analysis. Results: MBR at these three dosages did not influence the appetite or growth of the hamsters. Liver enzymes, blood glucose, total cholesterol, triglyceride, and liver weight were significantly reduced in the MBR groups than in the control group. Additionally, high-density lipoprotein-cholesterol (HDL-C) was also elevated in all MBR groups. On the other hand, serum low-density lipoprotein-cholesterol (LDL-C) was decreased in the MBR groups. Triglyceride (TG) in liver tissue and fatty liver level were lower in group H. Memory-associated proteins, phosphorylation of calmodulin-dependent protein kinase II (p-CaMK II) and synaptophysin (SYP), were increased in the brains of MBR groups. Conclusion: The high yield- and short procedure-produced MBR has the potential to protect animals fed with HFD from hyperlipidemia, hepatic steatosis, hyperglycemia, and synaptic impairment, which might be beneficial for patients with these types of diseases.


Assuntos
Fígado Gorduroso , Hiperlipidemias , Animais , Antioxidantes/farmacologia , Biotransformação , Glicemia/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/farmacologia , HDL-Colesterol , LDL-Colesterol , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/etiologia , Fígado , Polifenóis/metabolismo , Polifenóis/farmacologia , Resveratrol/farmacologia , Sinaptofisina/metabolismo , Triglicerídeos
11.
Int J Clin Oncol ; 27(6): 1013-1024, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35482171

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths in the world. Non-small cell lung cancer (NSCLC) accounts for 85% of all lung cancer cases. For lack of conveniently sensitive and specific biomarkers, the majority of patients are in the late stage at initial diagnosis. Long non-coding RNAs (LncRNAs), a novel type of non-coding RNA, have recently been recognized as critical factors in tumor initiation and progression, but the role of exosomal LncRNAs has not been thoroughly excavated in NSCLC yet. METHODS: We isolated exosomes from the serum of patients with NSCLC and healthy controls. Exosome RNA deep sequencing was subsequently performed to detect differentially expressed exosomal LncRNAs. qRT-PCR assay was then utilized to validate dysregulated LncRNAs in both testing and multicentric validation cohort. Receiver operating characteristic (ROC) curve was used to detect the diagnostic capability of exosomal biomarkers. Furthermore, Kaplan-Meier analysis was applied to evaluate the prognostic values of these molecules. RESULTS: On the basis of analysis, we found that novel exosomal LncRNA RP5-977B1 exhibited higher levels in NSCLC than that in the healthy controls. The area under the curve (AUC) value of exosomal RP5-977B1 was 0.8899 and superior to conventional biomarkers CEA and CYFRA21-1 both in testing and multicentric validation cohort. Interestingly, the diagnostic capability of exosomal RP5-977B1 was also validated in early-stage patients with NSCLC. Furthermore, high expression of exosomal RP5-977B1was closely related with worse prognosis in NSCLC (P = 0.036). CONCLUSIONS: Our results suggested that exosomal RP5-977B1 might serve as a novel "liquid biopsy" diagnostic and prognostic biomarker to monitor NSCLC and improve possible therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , RNA Longo não Codificante , Antígenos de Neoplasias , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Prognóstico , RNA Longo não Codificante/genética
12.
Psychol Health Med ; 27(2): 312-324, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33779436

RESUMO

The aims of the study were to assess the contribution of resilience, coping style, and COVID-19 stress on the quality of life (QOL) in frontline health care workers (HCWs). The study was a cross-sectional surveyperformed among 309 HCWs in a tertiaryhospital during the outbreak of COVID-19 in China. Data were collected through an anonymous, self-rated questionnaire, including demographic data, a 10-item COVID-19 stress questionnaire, Generic QOL Inventory-74, Connor-Davidson Resilience Scale, and the Simplified Coping Style Questionnaire. Hierarchical regression was used to analyse the relationship between the study variables and the QOL. Among the 309 participants, resilience and active coping were positively correlated with the QOL (P<0.001), whereas, working in confirmed case wards, COVID-19 stress, and passive coping were negatively correlated with the QOL (P<0.001). Resilience and the active coping were negatively correlated with COVID-19 stress (P<0.001). Resilience, coping style,and COVID-19 stressaccounted for 32%, 13%, and 8% of the variance in predicting the Global QOL, respectively. In conclusion, working in confirmed COVID-19 case wards and COVID-19 stress impaired the QOL in HCWs. Psychological intervention to improve the resilience and coping style, and reduce COVID-19 stress are important in improving the QOL and mental health of HCWs.


Assuntos
COVID-19 , Resiliência Psicológica , Adaptação Psicológica , COVID-19/epidemiologia , Estudos Transversais , Pessoal de Saúde/psicologia , Humanos , Qualidade de Vida , SARS-CoV-2
13.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362251

RESUMO

Pollen grains, the male gametophytes for reproduction in higher plants, are vulnerable to various stresses that lead to loss of viability and eventually crop yield. A conventional method for assessing pollen viability is manual counting after staining, which is laborious and hinders high-throughput screening. We developed an automatic detection tool (PollenDetect) to distinguish viable and nonviable pollen based on the YOLOv5 neural network, which is adjusted to adapt to the small target detection task. Compared with manual work, PollenDetect significantly reduced detection time (from approximately 3 min to 1 s for each image). Meanwhile, PollenDetect can maintain high detection accuracy. When PollenDetect was tested on cotton pollen viability, 99% accuracy was achieved. Furthermore, the results obtained using PollenDetect show that high temperature weakened cotton pollen viability, which is highly similar to the pollen viability results obtained using 2,3,5-triphenyltetrazolium formazan quantification. PollenDetect is an open-source software that can be further trained to count different types of pollen for research purposes. Thus, PollenDetect is a rapid and accurate system for recognizing pollen viability status, and is important for screening stress-resistant crop varieties for the identification of pollen viability and stress resistance genes during genetic breeding research.


Assuntos
Aprendizado Profundo , Melhoramento Vegetal , Pólen , Software , Temperatura Alta
14.
Int J Mol Sci ; 23(6)2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35328797

RESUMO

Anther indehiscence and pollen sterility caused by high temperature (HT) stress have become a major problem that decreases the yield of cotton. Pollen- and anther-specific genes play a critical role in the process of male reproduction and the response to HT stress. In order to identify pollen-specific genes that respond to HT stress, a comparative transcriptome profiling analysis was performed in the pollen and anthers of Gossypium hirsutum HT-sensitive Line H05 against other tissue types under normal temperature (NT) conditions, and the analysis of a differentially expressed gene was conducted in the pollen of H05 under NT and HT conditions. In total, we identified 1111 pollen-specific genes (PSGs), 1066 anther-specific genes (ASGs), and 833 pollen differentially expressed genes (DEGs). Moreover, we found that the late stage of anther included more anther- and pollen-specific genes (APSGs). Stress-related cis-regulatory elements (CREs) and hormone-responsive CREs are enriched in the promoters of APSGs, suggesting that APSGs may respond to HT stress. However, 833 pollen DEGs had only 10 common genes with 1111 PSGs, indicating that PSGs are mainly involved in the processes of pollen development and do not respond to HT stress. Promoters of these 10 common genes are enriched for stress-related CREs and MeJA-responsive CREs, suggesting that these 10 common genes are involved in the process of pollen development while responding to HT stress. This study provides a pathway for rapidly identifying cotton pollen-specific genes that respond to HT stress.


Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium , Flores/metabolismo , Perfilação da Expressão Gênica , Gossypium/metabolismo , Pólen/genética , Temperatura , Transcriptoma
15.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500553

RESUMO

This review describes recent advances in copper-catalyzed difluoroalkylation reactions. The RCF2 radical is generally proposed in the mechanism of these reactions. At present, various types of copper-catalyzed difluoroalkylation reactions have been realized. According to their characteristics, we classify these difluoroalkylation reactions into three types.


Assuntos
Cobre , Ciclização , Catálise , Estrutura Molecular
16.
J Integr Plant Biol ; 64(10): 2009-2025, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35929662

RESUMO

The double-recessive genic male-sterile (ms) line ms5 ms6 has been used to develop cotton (Gossypium hirsutum) hybrids for many years, but its molecular-genetic basis has remained unclear. Here, we identified the Ms5 and Ms6 loci through map-based cloning and confirmed their function in male sterility through CRISPR/Cas9 gene editing. Ms5 and Ms6 are highly expressed in stages 7-9 anthers and encode the cytochrome P450 mono-oxygenases CYP703A2-A and CYP703A2-D. The ms5 mutant carries a single-nucleotide C-to-T nonsense mutation leading to premature chain termination at amino acid 312 (GhCYP703A2-A312aa ), and ms6 carries three nonsynonymous substitutions (D98E, E168K, and G198R) and a synonymous mutation (L11L). Enzyme assays showed that GhCYP703A2 proteins hydroxylate fatty acids, and the ms5 (GhCYP703A2-A312aa ) and ms6 (GhCYP703A2-DD98E,E168K,G198R ) mutant proteins have decreased enzyme activities. Biochemical and lipidomic analyses showed that in ms5 ms6 plants, C12-C18 free fatty acid and phospholipid levels are significantly elevated in stages 7-9 anthers, while stages 8-10 anthers lack sporopollenin fluorescence around the pollen, causing microspore degradation and male sterility. Overall, our characterization uncovered functions of GhCYP703A2 in sporopollenin formation and fertility, providing guidance for creating male-sterile lines to facilitate hybrid cotton production and therefore exploit heterosis for improvement of cotton.


Assuntos
Gossypium , Infertilidade das Plantas , Aminoácidos/metabolismo , Códon sem Sentido/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Fertilidade/genética , Regulação da Expressão Gênica de Plantas/genética , Gossypium/genética , Gossypium/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Nucleotídeos/metabolismo , Fosfolipídeos/metabolismo , Infertilidade das Plantas/genética
17.
Univers Access Inf Soc ; : 1-16, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36530862

RESUMO

With the development of technology and demand for online courses, there have been considerable quantities of online, blended, or flipped courses designed and provided. However, in the technology-enhanced learning environments, which are also full of social networking websites, shopping websites, and free online games, it is challenging to focus students' attention and help them achieve satisfactory learning performance. In addition, the instruction of programming courses constantly challenges both teachers and students, particularly in online learning environments. To overcome and solve these problems and to facilitate students' learning, the researchers in this study integrated two teaching approaches, using meta-cognitive learning strategy (MCLS) and team regulation (TR), to develop students' regular learning habits and further contribute to their programming skills, academic motivation, and refusal self-efficacy of Internet use, in a cloud classroom. In this research, a quasi-experiment was conducted to investigate the effects of MCLS and TR adopting the experimental design of a 2 (MCLS vs. non-MCLS) × 2 (TR vs. non-TR) factorial pre-test/post-test. In this research, the participants consisted of four classes of university students from non-information or computer departments enrolled in programming design, a required course. The experimental groups comprised three of the classes, labelled as G1, G2, and G3. G1 concurrently received both the online MCLS and TR intervention, while G2 only received the online MCLS intervention, and G3 only received the online TR intervention. Serving as the control group, the fourth class (G4) received traditional teaching. This study investigated the effects of MCLS, TR, and their combination, on improving students' programming skills, academic motivation, and refusal self-efficacy of Internet use in an online computing course. According to the results, students who received online TR significantly enhanced their programming design skills and their refusal self-efficacy of Internet use a cloud classroom. However, the expected effects of MCLS on developing students' programming skills, academic motivation, and refusal self-efficacy of Internet use were not found in this study. The teaching strategy of integrating MCLS and TR in an online programming course in this study can serve as a reference for educators when conducting online, blended, or flipped courses during the COVID-19 pandemic.

18.
BMC Genomics ; 22(1): 277, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865322

RESUMO

BACKGROUND: Heterosis has been exploited for decades in different crops due to resulting in dramatic increases in yield, but relatively little molecular evidence on this topic was reported in cotton. RESULTS: The elite cotton hybrid variety 'Huaza Mian H318' (H318) and its parental lines were used to explore the source of its yield heterosis. A four-year investigation of yield-related traits showed that the boll number of H318 showed higher stability than that of its two parents, both in suitable and unsuitable climate years. In addition, the hybrid H318 grew faster and showed higher fresh and dry weights than its parental lines at the seedling stage. Transcriptome analysis of seedlings identified 17,308 differentially expressed genes (DEGs) between H318 and its parental lines, and 3490 extremely changed DEGs were screened out for later analysis. Most DEGs (3472/3490) were gathered between H318 and its paternal line (4-5), and only 64 DEGs were found between H318 and its maternal line (B0011), which implied that H318 displays more similar transcriptional patterns to its maternal parent at the seedling stage. GO and KEGG analyses showed that these DEGs were highly enriched in photosynthesis, lipid metabolic, carbohydrate metabolic and oxidation-reduction processes, and the expression level of these DEGs was significantly higher in H318 relative to its parental lines, which implied that photosynthesis, metabolism and stress resistances were enhanced in H318. CONCLUSION: The enhanced photosynthesis, lipid and carbohydrate metabolic capabilities contribute to the heterosis of H318 at the seedling stage, and establishes a material foundation for subsequent higher boll-setting rates in complex field environments.


Assuntos
Gossypium , Vigor Híbrido , Carboidratos , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Vigor Híbrido/genética , Fotossíntese/genética
19.
BMC Plant Biol ; 21(1): 229, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022812

RESUMO

BACKGROUND: Casein kinase I (CKI) is a kind of serine/threonine protein kinase highly conserved in plants and animals. Although molecular function of individual member of CKI family has been investigated in Arabidopsis, little is known about their evolution and functions in Gossypium. RESULTS: In this study, five cotton species were applied to study CKI gene family in cotton, twenty-two species were applied to trace the origin and divergence of CKI genes. Four important insights were gained: (i) the cotton CKI genes were classified into two types based on their structural characteristics; (ii) two types of CKI genes expanded with tetraploid event in cotton; (iii) two types of CKI genes likely diverged about 1.5 billion years ago when red and green algae diverged; (iv) two types of cotton CKI genes which highly expressed in leaves showed stronger response to photoperiod (circadian clock) and light signal, and most two types of CKI genes highly expressed in anther showed identical heat inducible expression during anther development in tetraploid cotton (Gossypium hirsutum). CONCLUSION: This study provides genome-wide insights into the evolutionary history of cotton CKI genes and lays a foundation for further investigation of the functional differentiation of two types of CKI genes in specific developmental processes and environmental stress conditions.


Assuntos
Caseína Quinase I/genética , Evolução Molecular , Gossypium/genética , Proteínas de Plantas/genética , Caseína Quinase I/metabolismo , Genoma de Planta , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Proteínas de Plantas/metabolismo
20.
New Phytol ; 231(1): 165-181, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33665819

RESUMO

Global warming has reduced the productivity of many field-grown crops, as the effects of high temperatures can lead to male sterility in such plants. Genetic regulation of the high temperature (HT) response in the major crop cotton is poorly understood. We determined the functionality and transcriptomes of the anthers of 218 cotton accessions grown under HT stress. By analyzing transcriptome divergence and implementing a genome-wide association study (GWAS), we identified three thermal tolerance associated loci which contained 75 protein coding genes and 27 long noncoding RNAs, and provided expression quantitative trait loci (eQTLs) for 13 132 transcripts. A transcriptome-wide association study (TWAS) confirmed six causal elements for the HT response (three genes overlapped with the GWAS results) which are involved in protein kinase activity. The most susceptible gene, GhHRK1, was confirmed to be a previously uncharacterized negative regulator of the HT response in both cotton and Arabidopsis. These functional variants provide a new understanding of the genetic basis for HT tolerance in male reproductive organs.


Assuntos
Estudo de Associação Genômica Ampla , Infertilidade Masculina , Gossypium/genética , Humanos , Masculino , Locos de Características Quantitativas/genética , Temperatura , Transcriptoma/genética
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