Genome-Wide Identification And Expression Analysis Of TCP Transcription Factors In Cotton

Abstract

TCP proteins are plant-specific transcription factors known to perform a variety of physiological functions during plant growth and development. In the current study, we performed for the first time the comprehensive analysis of TCP gene family in two sequenced cotton species, Gossypium raimondii and Gossypium arboreum, including phylogenetic analysis, chromosome location, gene duplication status, gene structure and conserved motif analysis, as well as expression profiles in different tissues and at different developmental stages. Our results showed that a total of 38 non-redundant cotton TCP encoding genes were identified in G. raimondii, unevenly distributing across 11 out of the 13 chromosomes, whereas G. arboreum contains 36 TCP genes, which distributed across all of the thirteen chromosomes. GrTCPs and GaTCPs within the same subclade of the phylogenetic tree shared similar exon/intron organization and motif composition. In addition, both segmental duplication and whole-genome duplication contributed significantly to the expansion of cotton TCPs. Moreover, most TCP genes exhibited tissue-specific expression profiles, which shed light on their functional divergence. Remarkably, many these TCP transcription factor genes are specifically expressed in cotton fiber during different developmental stages, including cotton fiber initiation and early development. This suggests that TCP genes may play important roles in cotton fiber development.