Structural organization of TFL1-like genes in representatives of the tribe Phaseoleae DC

Abstract

The type of stem growth is one of the key features in determining plant architectonics. Stem growth type is an economically important trait. It interconnects with stem length, flowering duration, yield, resistance to lodging, and suitability of mechanized cultivation. Mutations in the TFL1 gene and its homologs have been demonstrated to change meristem indeterminacy across genera. The aim of this work was to characterize and compare the structural organization of TFL1- like genes in representatives of the tribe Phaseoleae (pigeonpea Cajanus cajan, soybean Glycine max, common bean Phaseolus vulgaris, adzuki bean Vigna angularis, mung bean V. radiata, and cowpea V. unguiculata) based on in silico analysis, including analysis of nucleotide sequences, predicted elements in promoter regions, predicted amino acid sequences, putative functional domains and 3D protein structures. We investigated TFL1 (one gene for adzuki bean, four copies for soybean, two copies for other studied species), ATC (two copies for soybean, one gene for other investigated species), and BFT (two copies for soybean, one gene for other studied species) gene family members found in whole-genome sequences databases available for representatives of the tribe Phaseoleae. The presence of duplicated copies for all genes in soybean may be a result of the last genome duplication event during the evolution of this species. Duplication of TFL1 gene to two copies in most of studied species of the tribe Phaseoleae is probably accompanied by the maintenance of the functional state of these genes. The exception is VrTFL1.2 of V. radiata, which likely had lost its functionality. This work broadens the existing data about the number of gene copies, their structural divergence and evolution, and the expected functional differences. This information will be important for understanding the molecular genetic mechanisms underlying the maintenance of indeterminacy in the growth of the shoot apical meristem, as well as in the control of the transition to the reproductive phase of plant development.