Characterization of Cotton Leaf miRNAs and Changes In miRNA Expression Associated with Heat Stress In Cotton as Determined by Deep Sequencing

Total RNA was prepared from either control (grown at 25 ^oC) or cotton leaves that were heat stressed at 42 ^oC for 4 or 24 hours.  Small RNA libraries were prepared and sequenced using an Illumina sequencer.  A total of approximately 7 million control  and 7 million heat stress primary reads were obtained from 2 genotypes differing in heat stress tolerance.  The putative mature miRNAs in these primary reads were determined and those making apparent precursor miRNAs were further analyzed to determine: 1) potential target genes regulated; 2) regulation of these miRNAs by heat stress; 3) differences in regulation in more heat stress tolerant and less heat stress tolerant genotypes.