Global evolution and expression analysis of BTB-containing ankyrin repeat genes in plants

Abstract

The ankyrin (ANK) repeat domain and bric-a-brac, tram-track, broad complex (BTB) domains, which are the most common protein motifs in eukaryotic proteins, regulate diverse developmental and biological processes in plants. In this study, 230 BTB-containing ANK (ANK-BTB) homologs were identified and categorized into two groups (class I and class II) in plants. Phylogenetic and comparative analysis found that ANK-BTB genes originated in bryophytes and ferns and their number expanded by segment duplications. All of the selected ANK-BTB genes were expressed in two or more tested tissues, indicating that these genes are involved in various aspects of developmental processes in Arabidopsis. Furthermore, the ANK-BTB genes responded to abiotic stresses (NaCl, mannitol, heat and cold) and ABA treatments. To our knowledge, this study is the first report of a genome-wide analysis of ANK-BTB genes. This study also provides valuable information to understand the classification, evolution and putative functions of the gene family.