ARS | Publication request: Distribution of fiber development genes and transcription factors between At and Dt subgenomes in tetraploid cotton

Submitted to: International Cotton Genome Initiative Workshop
Publication Type: Abstract Only
Publication Acceptance Date: June 21, 2010
Publication Date: N/A

Technical Abstract: As the worlds leading natural material used in the manufacture of textiles, cotton fibers are important seed trichomes derived from individual cells of the epidermal layer of the seed coat. Cotton fiber development is determined by large numbers of genes and transcription factors. However, little is known about how these genetic elements are distributed or organized between At and Dt subgenomes of the tetraploid AD genome. An integrated genome map of fiber genes was constructed to investigate the organization and evolution of such genes whose functions were previously verified and confirmed. A total of 535 cotton fiber genes, including 103 fiber transcription factors, 259 fiber development genes, and 173 SSR-contained fiber ESTs, were analyzed at the subgenome level. A total of 499 contigs were assembled and they covered about 151 Mb in physical length which represented about 6.7% of the AD cotton genome. Among them, 397 contigs were anchored into individual chromosomes. Results indicate that more fiber development genes were from subgenomes At than Dt while more transcription factors from subgenomes Dt than At. It is suggested that after merging of two diploid Gossypium genomes that subgenome At, functioning similarly as its probable A diploid ancestor (G. arboreum) that by itself produces fiber, provides more genes for fiber development. On the other hand, subgenome Dt, with its probable D diploid ancestor (G. raimondii) that by itself cannot produce fiber, provides more transcription factors that regulate the expression of the fiber genes in the subgenome At. The resulting integrated map of fiber genes would provide a framework to study individual full-length fiber genes and their dynamic gene networks that are interacted during the process of fiber development in the tetraploid cotton.