Project description:A cDNA library from 0-10 day post anthesis cotton ovules was established to study genes expressed in cotton ovule during initiation and quickly elongation period. We randomly sequenced over 100,000 ESTs from this library and acquired a gene pool of more than 28,000 UniESTs. The cotton UniESTs were then PCR-amplified and printed onto microarray. This array is comprised of about 28000 high-quality cotton cDNAs (with average length>750bp) and external controls. To study the different growth potential of cotton fibers in a one-year cycle, we then hybridized the array with RNA samples derived from +7 DPA wild-type upland cotton fibers in four different seasons, respectively.
Project description:Sea-island cotton (Gossypium barbadense L.) has superior fiber quality properties such as length, fineness and strength, while Upland cotton (Gossypium hirsutum L.) is characterized by high yield. To reveal features of Upland cotton and Sea-island cotton fiber cells, differential genes expression profiles during fiber cell elongation and in secondary wall deposits were established using cDNA microarray technology. This research provides a valuable genomic resource to deepen our understanding of the molecular mechanisms of cotton fiber development, and may ultimately lead to improvements in cotton fiber quality and yield.
Project description:Sea-island cotton (Gossypium barbadense L.) has superior fiber quality properties such as length, fineness and strength, while Upland cotton (Gossypium hirsutum L.) is characterized by high yield. To reveal features of Upland cotton and Sea-island cotton fiber cells, differential genes expression profiles during fiber cell elongation and in secondary wall deposits were established using cDNA microarray technology. This research provides a valuable genomic resource to deepen our understanding of the molecular mechanisms of cotton fiber development, and may ultimately lead to improvements in cotton fiber quality and yield. 15 samples were prepared for microarray slides hybridized with three biological replicate samples including a swap-dye experiment for each growth stage. Each spot had a repeat in the microarray slideM-oM-<M-^Ltherefore, data for six replicate experiments performed with biologically independent samples.
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: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: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:Two fiber tissues harvested 10 days post anthesis from upland cotton trees grown under the same green house conditions except for different seasons of the year were used for RNA extraction. Small RNA molecules under 30 bases were amplified and isolated from an agarose gel. The purified DNA was used directly for cluster generation and sequencing analysis using the Illumina Genome Analyzer according to the manufacturer's instructions. The 35nt sequence tags from sequencing went through data cleaning first, which included getting rid of the low-quality tags and several kinds of contaminants from the 35nt tags. All clean tag sequences with copy numbers were then summarized into a fasta format file. Fiber samples from different seasons were used for small RNA sequencing and data processing.
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% A bi-directional double-loop experimental design was adopted for the microarray analysis (Kerr and Churchill, 2001; Glonek, 2004) to analyze all possible significant changes in gene expression between any two developmental time points,. The double loop design guarantees that the two time points before and after each individual time point will have direct comparisons with multiple paths available to compare any two points. Self-hybridization control experiments between independent RNA isolations for each developmental stage demonstrated a high degree of reproducibility