Project description:Cotton is one of the most commercially important Fiber crops in the world and used as a source for natural textile Fiber and cottonseed oil. The fuzzless-lintless ovules of cotton mutants are ideal source for identifying genes involved in Fiber development by comparing with Fiber bearing ovules of wild-type. To decipher molecular mechanisms involved in Fiber cell development, transcriptome analysis has been carried out by comparing G. hirsutum cv. MCU5 (wild-type) with its fuzzless-lintless mutant (MUT). Cotton bolls were collected at Fiber initiation (0 dpa/days post anthesis), elongation (5, 10 and 15 dpa) and secondary cell wall synthesis stage (20 dpa) and gene expression profiles were analyzed in wild-type and MUT using Affymetrix cotton GeneChip Genome array.
Project description:Cotton is one of the most commercially important Fiber crops in the world and used as a source for natural textile Fiber and cottonseed oil. The fuzzless-lintless ovules of cotton mutants are ideal source for identifying genes involved in Fiber development by comparing with Fiber bearing ovules of wild-type. To decipher molecular mechanisms involved in Fiber cell development, transcriptome analysis has been carried out by comparing G. hirsutum cv. MCU5 (wild-type) with its fuzzless-lintless mutant (MUT). Cotton bolls were collected at Fiber initiation (0 dpa/days post anthesis), elongation (5, 10 and 15 dpa) and secondary cell wall synthesis stage (20 dpa) and gene expression profiles were analyzed in wild-type and MUT using Affymetrix cotton GeneChip Genome array. Cotton plants were grown under field condition. Flowers were tagged and cotton bolls were collected during Fiber development stages. Total RNA was isolated from Fiber bearing ovules of wild-type (WT) and fuzzless-lintless ovules of mutant (MUT) collected at various (0, 5, 10, 15 and 20 dpa) Fiber development stages using SpectrumTM Plant Total RNA kit (Sigma, USA) according to the manufacturerM-bM-^@M-^Ys protocol. Affymetrix cotton GeneChip Genome array (Affymetrix, USA) having 23,977 probe sets representing 21,854 cotton transcripts was used for transcriptome analysis. Three biological replicates were maintained to test the reproducibility and quality of the chip hybridization. cDNA labeling, array hybridization, staining and washing procedures were carried out as described in the Affymetrix protocols. CEL files having estimated probe intensity values were analyzed with GeneSpring GX-11.5 software (Agilent Technologies, USA) to get differentially expressed transcripts. The Robust Multiarray Average (RMA) algorithm was used for the back ground correction, quantile normalization and median polished probe set summarization to generate single expression value for each probe set. Normalized expression values were log2-transformed and differential expression analysis was performed using unpaired t-test. The p-values were corrected by applying the false discovery rate (FDR) correction (Benjamini and Hochberg, 2000).
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: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:Transcriptome analysis in cotton during fibre development stages. To study the molecular response of drought stress in cotton under field condition global gene expression analysis was carried out at fibre development stages (0, 5, 10 and 20 dpa/Days post anthesis). Gossypium hirsutum cv. Bikaneri Nerma was used for the gene expression analysis. Cotton plants were subjected to drought stress at peak flowering stage. Samples were collected when the soil moisture content was 19.5% which is 50% of the normal control plots. Gene expression profiles in drought induced and their respective control samples were analyzed using Affymertix cotton Genechip Genome arrays to study the global changes in the expression of genome. Total RNA was isolated from 0 dpa, 5 dpa, fibre bearing ovules of 10 dpa, and fibre bearing ovules of 20 dpa. Samples were collected from both drought induced and control plants. Biotin labeled cRNA was hybridized on Affymertix cotton Genechip Genome array following the Affymetrix protocols. Three biological replicates were maintained.
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.