Project description:Upland cotton (Gossypium hirsutum L.) is one of the world’s most important fiber crops, accounting for more than 90% of all cotton production. While their wild progenitors have relatively short and coarse, often tan-colored fibers, modern cotton cultivars possess longer, finer, stronger, and whiter fiber. In this study, the wild and cultivated cottons (YU-3 and TM-1) selected show significant differences on fibers at 10 day post-anthesis (DPA), 20 DPA and mature stages at the physiological level. In order to explore the effects of domestication, reveal molecular mechanisms underlying these phenotypic differences and better inform our efforts to further enhance cotton fiber quality, an iTRAQ-facilitated proteomic methods were performed on developing fibers. There were 6990 proteins identified, among them 336 were defined as differentially expressed proteins (DEPs) between fibers of wild versus domesticated cotton. The down- or up-regulated proteins in wild cotton were involved in Phenylpropanoid biosynthesis, Zeatin biosynthesis, Fatty acid elongation and other processes. Association analysis between transcroptome and proteome showed positive correlations between transcripts and proteins at both 10 DPA and 20 DPA. The difference of proteomics had been verified at the mRNA level by qPCR, also at physiological and biochemical level by POD activity determination and ZA content estimation. This work corroborate the major pathways involved in cotton fiber development and demonstrate that POD activity and zeatin content have a great potential related to fiber elongation and thickening.
Project description:This study was initiated with the objective of identifying the anther/tapetum specific promoters from cotton floral buds. Cotton is an important commercial crop. Hybrid cotton varieties are developed to obtain improved yield and fiber quality. Most of the hybrid seed production in cotton is carried out by hand emasculation, which requires large amount of manpower, resulting in high cost of hybrid seed. We are developing barnase-barstar based male sterility system, which would be a better alternative for hybrid development. The tapetum specific promoters are main requirement for such a system. The study was thus carried out to identify genes expressed in the anthers.
Project description:Cotton fiber were used for the expression analysis at different developmental stages Affymetrix Cotton Genome array were used for the global profiling of gene expression of cotton fiber at different developmental stages
Project description:Purpose: The goal of this experiment was to use RNA-seq to compare the two commercial cotton species Gossypium hirsutum and Gossypium barbadense and determine what transcripts may account for the better fiber quality in the latter. Methods: RNA was extracted from Gossypium barbadense or Gossypium hirsutum fibers at 10, 15, 18, 21, and 28 days post anthesis. Paired-end, 100-bp RNA-seq was performed on an Illumina HiSeq2000 and the reads were mapped to the Gossypium raimondii genome at www.phytozome.net and non-homologous contig assemblies from Gossypium arboreum. Results from RNA-seq were combined with non-targeted metabolomics. Results: Approximately 38,000 transcripts were expressed (RPKM>2) in each fiber type and approximately 2,000 of these transcripts were differentially expressed in a cross-species comparison at each timepoint. Enriched Gene Ontology biological processes in differentially expressed transcripts suggested that Gh fibers were more stressed. Conclusions: Both metabolomic and transcriptomic data suggest that better mechanisms for managing reactive oxygen species contribute to the increased fiber length in Gossypium barbadense. This appears to result from enhanced ascorbate biosynthesis via gulono-1,4-lactone oxidase and ascorbate recycling via dehydroascorbate reductase. See Bioproject PRJNA263926 and SRA accession SRP049330 for study design and raw sequencing data and Bioproject PRJNA269608 and TSA accession GBYK00000000 for Gossypium arboreum assembled contig sequences used for transcriptome mapping - Cotton fiber mRNA from 10,15,18,21 and 28 day post anthesis fiber from either Gossypium hirusutm or Gossypium barbadense was sequenced and differential gene expression analysis was conducted between species for each timepoint and between adjacent timepoints. Each timepoint was representative of fiber from 9 individual plants processed as 3 biological replicate pools (material from 3 individual plants per pool).
Project description:In order to study gene expression at the genomic level during elongation and secondary cell wall synthesis of upland cotton fiber, oligonucleotide microarrays were employed. RNA was isolated from fibers in 7 different time points beginning prior to peak fiber expansion, continuing through termination of fiber expansion and ending at peak cellulose synthesis (5, 8, 10, 14, 17, 21, and 24dpa). The arrays contained ~25,000 oligonucleotides representing ~12,200 genes designed from a fiber EST database during peak cell expansion. Dynamic changes in gene expression were analyzed in a developmental context to identify stage-specific biological processes and pathways likely to be crucial to cell polar elongation or cellulose biosynthesis and secondary cell wall biogenesis. Genes with significant changes in expression relative to any preceding time point were identified (moderated t-statistics, adjusted p-value <0.05) for each developmental time point with an expected false discovery rate for multiple testing <5%
Project description:Cotton (Gossypium hirsutum) is widely distributed worldwide, and improving the quality of its fiber is one of the most important tasks in cotton breeding. Cotton fibers are primarily composed of cellulose, which is synthesized and regulated by cellulose synthase (CesAs). However, the molecular mechanism of CesA genes in cotton is unclear. In this study, the cotton transcriptome and metabolome were used to investigate the significant function of CesA genes in fiber development. Finally, 321 metabolites were obtained, 84 of which were associated with the corresponding genes. Interestingly, a target gene named Gh_A08G144300, one of the CesA gene family members, was closely correlated with the development of cotton fibers. Then, identification and functional analysis were conducted. The target CesA gene Gh_A08G144300 was selected and analysed to determine its specific function in cotton fiber development. High-level gene expression of Gh_A08G144300 was found at different fiber development stages by RNA-seq analysis, and the silencing of Gh_A08G144300 visibly inhibited the growth of cotton fibers, showing that it is critical for their growth. This study provides an important reference for research on the gene function of Gh_A08G144300 and the regulatory mechanism of fiber development in cotton.
Project description:Naturally brown-colored upland cotton is used in specific textile industries. The color results from condensed tannin formed by proanthocyanidin (PA) oxidation. However, the roles of PA biosynthesis and glucose metabolism in brown pigmentation are unclear. Here, we integrated proteomes and metabolomes of fibers collected at 0, 10, 20 and 30 days post-anthesis (DPA) from a brown-colored cotton line (Z161) and its near-isogenic white-colored cotton line (RT). Compared with in RT, all the proteins in the flavonoid biosynthetic pathway in Z161 were highly accumulated. The metabolome data showed that the epi-flavan-3-ols in most of the brown fibers. Significantly lower levels of catalytic enzymes of the starch and sucrose metabolic pathway, which affects cellulose biosynthesis, were found in Z161 compared with in RT, except endoglucanase and uridine-5'-diphosphate (UDP)-D-glucose pyrophosphorylase