An Overview on Advances in Cotton Genome and Regulation of Fiber Development

In the evolution of flowering plants major driving forces for the evolution is polyploidy and whole-genome duplication. The genus Gossypium contains 45 diploid (2n=26) and six tetraploid (2n=52) species. During evolution, polyploidy (allo-tetraploidy) enhanced the fiber traits in allo-tetraploids as compared to diploids, resulting in higher fiber yield and quality. The advancement of G. hirsutum genome into AD-genome (allo-tetraploid) brings by the polyploidization event between diploid progenitors of A- and D-genome. The genome size of G. raimondii and G. arboreum is 880Mb and 1, 700Mb respectively reveals that the size of D-genome is lesser than the genome size of A-genome. Initiation and elongation are the best understood developmental stages at the transcriptional level among different stages of fiber development. However, scanty knowledge is available about the SCW stage-specific transcriptional regulation and its detailed molecular mechanism. Since specific promoters regulates transcription in fiber cells hence the knowledge of novel fiber specific regulatory elements along promoters and their interacting transcription factors might be a better tool to be used in the genetic manipulation of fiber quality parameters.