Project description:RNAs from the upland cotton 9-DPA fibers were compared to the 9-DPA fiber-detached ovule. RNAs from the upland cotton 9-DPA fibers were compared to the 9-DPA fiber-detached ovule.
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:We performed a comparative genomics approach between im mutant and TM-1 in order to understand the function of im gene reducing the degree of fiber cell wall development. We compared transcriptome profiles of developing fibers (10, 17, and 28 days post anthesis (DPA)) between two NILs using Affymetrix cotton array chip containing 21,854 transcripts.
Project description:To get glance to the events of the fast elongation and second cell wall synthesis stages of developing cotton fiber cells, we examined expression patterns of over 5000 genes by cDNA array from 3 to 18 DPA in a 3-day interval. RNAs from the 3-, 6-, 9-, 12-, 15-, and 18-DPA fibers were compared to the 9-DPA fiber RNA for time-course analysis. Four biological repeats were carried out including two dye-swap ones.
Project description:Compare the expression profiles of natural brown and green cotton fibers, and white color fiber at 0 and 12 days post-anthesis (DPA) to identify genes involved in pigment synthesis
Project description:This experiment was designed to investigate the molecular basis of cotton fiber cell initiation. 32,000 ESTs were sequenced from Gossypium hirsutum L. TM-1 immature ovules (GH_TMO) and developed cotton oligonucleotide microarrays containing ~23,000 unigenes. Transcriptome analyses were performed to compare gene expression changes in laser capture microdissected fiber cell initials (or epidermis) and inner ovules. The gene expression profiles of the fiber cell initials were compared with those of the inner ovules in each developmental stage prior to, right at, and shortly after the initiation of fiber cells. Many genes in various molecular function or biological processes were over- or under-represented between fibers and non-fiber tissues in each developmental stage, suggesting temporal regulation of gene expression during early stages of fiber development. For gene expression studies using a large set cotton oligo-microarray, 4 developmental stages were chosen. To study differential expression during fiber initiation, ovules at -2 DPA, 0 DPA, and 2 DPA were used. One of the fiber elongation stage tissues (7 DPA) was included. In each developmental stage, epidermis was separated from inner ovules and subjected to the hybridization. In addition, epidermis and ovule comparisons were performed individually with 0 DPA as a control point for comparison.
Project description:To identify potential miRNAs involved in fiber development and elucidate their expression differences between G. barbadense and G. hirsutum, we constructed two small RNA libraries, Gb10 and Gh10, prepared from fibers of 3-79 (G. barbadense) and TM-1 (G. hirsutum) collected at 10 days post-anthesis (DPA). We identified 28 conserved miRNA families, including 24 that exactly match known plant miRNA families in miRBase. With MIREAP and newly developed software miRsearcher, 7 candidate-novel miRNAs were found. 5 candidate-novel miRNAs were expressed in both species, 2 candidate-novel miRNAs were expressed only in one species. Moreover, 4 miRNA families showed significant expression differences between sea-island cotton and upland cotton in 10 DPA fibers. two examples including 3-79 and TM-1 10 DPA fibers
Project description:Transcriptional profiling of cotton fibers during development. Time course at 6 days post anthesis (dpa), 10 dpa, 20 dpa, and 24 dpa. All referenced to 20 dpa.
Project description:exceptional example of evolutionary innovation is the single-celled seed trichome in Gossypium ("cotton fiber"). We have used fiber development in Gossypium as a system to understand how morphology can rapidly evolve. Fiber has undergone considerable morphological changes between the short, tightly adherent fibers of G. longicalyx and the derived long, spinable fibers of its closest relative, G. herbaceum, that facilitated cotton domestication. We conducted comparative gene expression profiling across a developmental time-course of fibers from G. longicalyx and G. herbaceum using microarrays with ~ 22,000 genes. Expression changes between stages were temporally protracted in G. herbaceum relative to G. longicalyx, reflecting a prolongation of the ancestral developmental program. Gene expression and GO analyses showed that many genes involved with stress responses were up-regulated early in G. longicalyx fiber development. Several candidate genes up-regulated in G. herbaceum have been implicated in regulating redox levels and cell elongation processes. Three genes previously shown to modulate hydrogen peroxide levels were consistently expressed in domesticated and wild cotton species with long fibers but expression was not detected by qRT-PCR in wild species with short fibers. Hydrogen peroxide is important for cell elongation, but at high concentrations it becomes toxic, activating stress processes that may lead to early onset of secondary cell wall synthesis and the end of cell elongation. These observations suggest that the evolution of long spinable fibers in cotton was accompanied by novel expression of genes assisting in the regulation of reactive oxygen species levels. Our data suggest a model for the evolutionary origin of a novel morphology through differential gene regulation causing prolongation of an ancestral developmental program. Keywords: Cotton, fiber, evolution, time-point, comparative genomic hybridization, stress response genes, H2O2 A balanced developmental loop design for microarray analysis was performed. For G. herbaceum (A1) and G. longicalyx (F), four fiber developmental time-points, 5, 10, 20 and 25 DPA were sampled. Within each species, hybridizations were performed between each pair of consecutive developmental stages by labeling one with Cy5 and the other with Cy3, and by closing the loop with a comparison of 25 and 5 dpa. In addition, 2 hybridizations were done between species at each time-point, using a dye swap for each pair. With three biological replications and 16 slides each, we generated gene expression data from a total of 48 microarrays.