Genome-wide identification of three-amino-acid-loop-extension gene family and their expression profile under hormone and abiotic stress treatments during stem development of Prunus mume

Abstract

Transcription factors encoded by the three-amino-acid-loop-extension (TALE) gene family play a key role in regulating plant growth and development, and are involved in plant hormone regulatory pathways and responses to various environmental stresses. Researchers are currently studying <i>TALE</i> genes in different species, but <i>Prunus mume</i> <i>TALE</i> genes have not yet been studied. Therefore, based on the <i>P. mume</i> genome, we found a total of 23 <i>TALE</i> gene family members, which were distributed on eight chromosomes. <i>TALE</i> genes contained the characteristic domains of this family, and could be divided into KNOTTED-like homeobox (KNOX) subfamily and BEL1-like homeobox (BELL) subfamily. They can form heterodimers with each other. Fragment duplication and tandem duplication events were the main reasons for the expansion of <i>P. mume</i> <i>TALE</i> gene family members and the <i>TALE</i> genes were selected by different degrees of purification. The inter-species collinearity analysis showed that the relationship between <i>P. mume</i> and other four <i>Prunus</i> species was consistent with the distance of origin. Eleven members of <i>P. mume</i> <i>TALE</i> genes were specifically highly expressed in stem, mainly at the early stage of stem development. The cis-element analysis showed that the promoter of <i>P. mume</i> <i>TALE</i> genes contained a variety of hormone and abiotic stress response elements, and four <i>TALE</i> genes responded to two kinds of abiotic stresses and four kinds of hormones at the early stage of stem development. In conclusion, this study lays a foundation to explore the role of <i>TALE</i> gene family in <i>P. mume</i> growth and development.