microRNA expression in salt-tolerant and salt-sensitive cotton cultivars under normal and salt-stressed conditions

To detect salt-tolerance-related miRNAs, comparative analysis of miRNA expression profiles was performed between the salt-tolerant and -sensitive cotton cultivars in control and salt-stressed conditions (treated with 300 mM NaCl for 24 h) using microRNA microarray Total RNA was extracted from (1) the seedling of salt-tolerant cotton cultivar in normal growth conditions, (2) the seedling of salt-tolerant cotton cultivar in salt-stressed growth conditions, (3) the seedling of salt-sensitive cotton cultivar in normal growth conditions, and (4) the seedling of salt-sensitive cotton cultivar in salt-stressed growth conditions. Then, the low-molecular-weight RNA (LMW-RNA) was isolated using the PEG solution precipitation method and used to hybridization.