Genome-wide investigation and expression pattern of family genes in cotton under low phosphorus stress.

Phosphorus starvation response (PHR) protein is an important transcription factor in phosphorus regulatory network, which plays a vital role in regulating the effective utilization of phosphorus. So far, the genes have not been systematically investigated in cotton. In the present study, we have identified 22, 23, 41 and 42 genes in , , and , respectively. Phylogenetic analysis showed that cotton genes were classified into five distinct subfamilies. The gene structure, protein motifs and gene expression were further investigated. The genes of from the same subfamily had similar gene structures, all containing Myb_DNA-binding and Myb_CC_LHEQLE conserved domain. The structures of paralogous genes were considerably conserved in exons number and introns length. The cis-element prediction in their promoters showed that genes were not only regulated by light induction, but also were related to auxin, MeJA, abscisic acid-responsive elements, of which might be regulated by miRNA. The expression analysis showed that the genes were differentially expressed in different tissues under various stresses. Furthermore, , , and were significantly changed under low phosphorus stress. The results of this study provide a basis for further cloning and functional verification of genes related to regulatory network of low phosphorus tolerance in cotton.