Genome-Wide Identification and Evolutionary Analysis of Gossypium YTH Domain-Containing RNA-Binding Protein Family and the Role of GhYTH8 in Response to Drought Stress

Abstract

YTH domain-containing proteins are one kind of RNA-binding protein involved in post-transcriptional regulation and play multiple roles in regulating the growth, development, and abiotic stress responses of plants. However, the YTH domain-containing RNA-binding protein family has not been previously studied in cotton. In this study, a total of 10, 11, 22, and 21 <i>YTH</i> genes were identified in <i>Gossypium arboreum</i>, <i>Gossypium raimondii</i>, <i>Gossypium barbadense</i>, and <i>Gossypium hirsutum</i>, respectively. These <i>Gossypium YTH</i> genes were categorized into three subgroups by phylogenetic analysis. The chromosomal distribution, synteny analysis, structures of <i>Gossypium YTH</i> genes, and the motifs of YTH proteins were analyzed. Furthermore, the <i>cis</i>-element of <i>GhYTH</i> genes promoter, miRNA targets of <i>GhYTH</i> genes, and subcellular localization of GhYTH8 and GhYTH16 were characterized. Expression patterns of <i>GhYTH</i> genes in different tissues, organs, and in response to different stresses were also analyzed. Moreover, functional verifications revealed that silencing <i>GhYTH8</i> attenuated the drought tolerance in the upland cotton TM-1 line. These findings provide useful clues for the functional and evolutionary analysis of <i>YTH</i> genes in cotton.