Open Access System for Information Sharing

Login Library

 

Article
Cited 27 time in webofscience Cited 29 time in scopus
Metadata Downloads

A Novel Prokaryote-Type ECF/ABC Transporter Module in Chloroplast Metal Homeostasis SCIE SCOPUS

Title
A Novel Prokaryote-Type ECF/ABC Transporter Module in Chloroplast Metal Homeostasis
Authors
LEE, YOUNGSOOKLena Vioith von VoithenbergJiyoung ParkChristopher LuxRoland StubeKatrin Philippar
Date Issued
2019-10
Publisher
FRONTIERS MEDIA SA
Abstract
During evolution, chloroplasts, which originated by endosymbiosis of a prokaryotic ancestor of today's cyanobacteria with a eukaryotic host cell, were established as the site for photosynthesis. Therefore, chloroplast organelles are loaded with transition metals including iron, copper, and manganese, which are essential for photosynthetic electron transport due to their redox capacity. Although transport, storage, and cofactor-assembly of metal ions in chloroplasts are tightly controlled and crucial throughout plant growth and development, knowledge on the molecular nature of chloroplast metal-transport proteins is still fragmentary. Here, we characterized the soluble, ATP-binding ABC-transporter subunits ABCI10 and ABCI11 in Arabidopsis thaliana, which show similarities to components of prokaryotic, multisubunit ABC transporters. Both ABCI10 and ABCI11 proteins appear to be strongly attached to chloroplast-intrinsic membranes, most likely inner envelopes for ABCI10 and possibly plastoglobuli for ABCI11. Loss of ABCI10 and ABCI11 gene products in Arabidopsis leads to extremely dwarfed, albino plants showing impaired chloroplast biogenesis and deregulated metal homeostasis. Further, we identified the membrane-intrinsic protein ABCI12 as potential interaction partner for ABCI10 in the inner envelope. Our results suggest that ABCI12 inserts into the chloroplast inner envelope membrane most likely with five predicted a-helical transmembrane domains and represents the membrane-intrinsic subunit of a prokaryotic-type, energy-coupling factor (ECF) ABC-transporter complex. In bacteria, these multisubunit ECF importers are widely distributed for the uptake of nickel and cobalt metal ions as well as for import of vitamins and several other metabolites. Therefore, we propose that ABCI10 (as the ATPase A-subunit) and ABCI12 (as the membrane-intrinsic, energy-coupling T-subunit) are part of a novel, chloroplast envelope-localized, AAT energy-coupling module of a prokaryotic-type ECF transporter, most likely involved in metal ion uptake.
URI
https://oasis.postech.ac.kr/handle/2014.oak/100453
DOI
10.3389/fpls.2019.01264
ISSN
1664-462X
Article Type
Article
Citation
FRONTIERS IN PLANT SCIENCE, vol. 10, 2019-10
Files in This Item:

qr_code

  • mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Related Researcher

Researcher

이영숙LEE, YOUNGSOOK
Dept of Life Sciences
Read more

Views & Downloads

Browse