A repeat region from the Brassica juncea HMA4 gene BjHMA4R is specifically involved in Cd²⁺ binding in the cytosol under low heavy metal concentrations.

ABSTRACT:

Background

HMA4 transporters are involved in the transport and binding of divalent heavy metals (Cd, Zn, Pb [lead] and Co [cobalt]). In general, as efflux pumps, HMA4 transporters can increase the heavy metal tolerance of yeast and Escherichia coli. Additional research has shown that the C-terminus of HMA4 contains a heavy metal-binding domain and that heterologous expression of a portion of peptides from this C-terminal domain in yeast provides a high level of Cd tolerance and Cd hyperaccumulation.

Results

We cloned BjHMA4 from Brassica juncea, and quantitative real-time PCR analysis revealed that BjHMA4 was upregulated by Zn and Cd in the roots, stems and leaves. Overexpression of BjHMA4 dramatically affects Zn/Cd distribution in rice and wheat seedlings. Interestingly, Bj

SUBMITTER: Wang J 

PROVIDER: S-EPMC6394093 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature