Working group session:
Functional Genomics
Presentation type:
oral
Authors:
Fang, Lei; Zhang, Tianzhen; Tian, Ruiping; Chen, Jiedan; Li, Xinhe; Wang, Sen; Wang, Peng
Presenter:
Fang, Lei
Correspondent:
Zhang, Tianzhen
Abstract:
Cotton fiber, a highly elongated, thickened single cell of the seed epidermis, is a powerful cell wall research model. Fiber length and strength are the key trait that determines fiber quality in cotton. To further reveal the mechanism of fiber length and strength formation, we used Digital Gene Expression Tag Profiling to compare transcriptome data from longer and/or stronger fiber chromosome introgressed lines (CSILs) containing segments of various Gossypium barbadense chromosomes with data from its recurrent parent TM-1 (from 5 DPA to 25 DPA). During the fiber elongation stage, a large number of differentially expressed genes (DEGs) involved in carbohydrate, fatty acid and secondary metabolism, particularly cell wall biosynthesis, were highly up-regulated, as determined by functional enrichment and pathway analysis. Furthermore, DEGs related to hormone responses and transcription factors showed up-regulated expression levels in the CSILs. During secondary cell wall stage, functional classification and enrichment analysis revealed that these DEGs were mainly enriched for secondary cell wall biogenesis and carbohydrate metabolism. In both stages, metabolic and regulatory network analysis indicated that the same pathways were differentially altered, and distinct pathways exhibited altered gene expression, in the CSILs. Our results provide important information about the molecular mechanisms controlling fiber length and strength, which are mainly tied to carbohydrate metabolism, cell wall biosynthesis, fatty acid metabolism, secondary metabolism, hormone responses and Transcription factors. Moreover, our results provide new insights into the critical factors associated with cell elongation and secondary cell wall biosynthesis, and facilitate further research aimed at understanding the mechanisms underlying cotton fiber length and strength.