Working group session:
Functional Genomics
Presentation type:
poster
Authors:
Liu, Nian; Tu, Lili; Tang, Wenxin; Gao, Wenhui; Lindsey, Keith; Zhang, Xianlong
Presenter:
Correspondent:
Zhang, Xianlong
Abstract:
microRNAs (miRNAs) are 20-24 nucleotide non-coding small RNAs that play important roles in plant development. The stages of cotton fiber development include initiation, elongation, secondary wall thickening and maturation. We constructed 7 fiber RNA libraries representing the initiation, elongation and second cell wall stages. A total of 47 conserved miRNA families and 7 novel miRNAs were profiled using small RNA sequencing. Northern blot and real-time PCR analyses revealed the dynamic expression of miRNAs during fiber development. In addition, 140 targets of 30 conserved miRNAs and 38 targets of 5 novel miRNAs were identified through degradome sequencing. Analysis of correlated expression between miRNAs and their targets demonstrated that specific miRNAs regulate transcription factors, SBP and MYB, a leucine-rich receptor-like protein kinase, a pectate lyase, α-tubulin, a UDP-glucuronic acid decarboxylase and cytochrome c oxidase subunit 1 to affect fiber development. Histochemical analyses showed that the biological activity of miRNA156/157 was specific in ovule and fiber development. Suppressing miRNA156/157 function resulted in the reduction of mature fiber length, illustrating that miRNA156/157 plays an essential role in fiber elongation. This study is the first to verify miRNA function in the cotton fiber.