Expression patterns and evidence of the expansion of Nicotiana tabacum L. TALE genes in the Solanaceae family

Abstract

The three-amino-acid-loop-extension (TALE) proteins are a class of transcription factors that regulate meristem differentiation during plant growth and development. In this study, we identified a total of 45 members of the tobacco TALE (NtTALE) transcription factor family. Based on domain type, the NtTALE genes were divided into BELL subfamily and KNOX subfamily. Cis-acting element analysis showed that the NtTALE gene promoters had a variety of response elements, including light-responsive elements, hormonal and abiotic stresses responsive elements, plant development related elements. Among the 45 NtTALE genes, the expression patterns of various plant tissues at different stages were different, 10 responded to alkali stress, 19 responded to dehydration treatment, 14 responded to cold stress, two responded to salt stress, and 17 responded to Ralstonia solanacearum infection. Phylogenetic analysis showed that the number of TALE genes in Nicotiana was significantly expanded compared with that in other Solanaceae. The KNOXIII subfamily members (NtTALE29, NtTALE45) were found only in Nicotiana tabacum. This study provides a theoretical basis for further research on the biological function of NtTALE genes.