Identification and bioinformatic analysis of Aux/IAAfamily based on transcriptome data of Bletilla striata

ABSTRACTAuxin/Indole-3-Acetic Acid (Aux/IAA) genes are involved in auxin signaling pathway and play an important role in plant growth and development. However, many studies focus on Aux/IAAgene families and much less known in Bletilla striata. In this study, a total of 27 Aux/IAAgenes (BsIAA1-27) were cloned from the transcriptome of Bletilla striata. Based on a phylogenetic analysis of the Aux/IAA protein sequences from B. striata, Arabidopsis thalianaand Dendrobium officinale, the Aux/IAAgenes of B. striata(BsIAAs) were categorized into 2 subfamilies and 9 groups. While BsIAAswere more closer to those of D. officinalecompared to A. thaliana. EST-SSR marker mining test showed that 4 markers could be stably amplified with obvious polymorphisms among 4 landraces. Our results suggested that BsIAAswere involved in the process of tuber development and provided insights into functional roles of Aux/IAAgenes in B. striataand other plants.