Genome-wide profiling of miRNAs and other small non-coding RNAs in the Verticillium dahliae inoculated cotton roots

MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) are short (19–25 nucleotides) non-coding RNA molecules that have large-scale regulatory effects on development and on stress responses in plants.The objective of this study is to investigate the transcriptional profile of miRNAs and other small non-coding RNAs in Verticillium–inoculated cotton roots. Four small RNA libraries were constructed from mocked and infected roots of two cotton cultured species which are with different Verticillium tolerance (‘Hai-7124’, Gossypium barbadense L., a Verticillium-tolerant cultivar, and ‘Yi-11’, Gossypium hirsutum L. a Verticillium-sensitive cultivar). The length distribution of obtained small RNA pools was significantly different among libraries. A total of 215 conserved miRNA families were identified in the two cotton species, of them 14 are novel. There were >65 families with different expression between two libraries. We also identified two ta-siRNAs and thousands of endogenous siRNA candidates, and hundred of them exhibited altered expression after inoculation of Verticillium. The profiling of these miRNAs and other small non-coding RNAs lay the foundation for further understanding of small RNAs function in the regulation of Verticillium defence responses in cotton roots. Examination of 2 different traetments in 2 cotton types.