Comparative and phylogenetic analysis of zinc transporter genes/proteins in plants

Abstract

Zinc is an important catalytic element for more than 300 enzymes and plays a structural role in the stabilization of many proteins. Protein domain analysis showed that identified Zn transporter proteins belong to the ZIP protein family (PF02535). Zn transporter sequences were found to have similar molecular weights (33.1-51.4 kDa) and amino acid lengths (306-478 amino acids) with 5.31-8.92 pI values. Subcellular localization of Zn transporters was predicted as the plasma membrane. They had 6-9 putative transmembrane domains with a variable region between TM-3 and TM-4, which could contain a potential histidine-rich metal-binding domain. Moreover, alignment analysis showed that the TM-2, -4, and -5 domains could be potential metal-binding sites because they contain highly conserved His residues. Based on a homology search, the retrieved sequences were identified as corresponding homologs of either Arabidopsis thaliana or Oryza sativa. Phylogenetic analysis also supported that A. thaliana and O. sativa sequences could be used as a reference/benchmark to identify Zn transporter homologs in various plant species. The findings of this study will be valuable theoretical knowledge for feature studies in terms of understanding the gene and protein features of Zn transporters in various plants.