Cargando…

Transport processes of the legume symbiosome membrane

The symbiosome membrane (SM) is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume:rhizobia symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is...

Descripción completa

Detalles Bibliográficos
Autores principales: Clarke, Victoria C., Loughlin, Patrick C., Day, David A., Smith, Penelope M. C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4266029/
https://www.ncbi.nlm.nih.gov/pubmed/25566274
http://dx.doi.org/10.3389/fpls.2014.00699
_version_ 1782348967459160064
author Clarke, Victoria C.
Loughlin, Patrick C.
Day, David A.
Smith, Penelope M. C.
author_facet Clarke, Victoria C.
Loughlin, Patrick C.
Day, David A.
Smith, Penelope M. C.
author_sort Clarke, Victoria C.
collection PubMed
description The symbiosome membrane (SM) is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume:rhizobia symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is the transport of a carbon energy source from plant to bacteroid in exchange for fixed nitrogen. At a biochemical level two channels have been implicated in movement of fixed nitrogen across the SM and a uniporter that transports monovalent dicarboxylate ions has been characterized that would transport fixed carbon. The aquaporin NOD26 may provide a channel for ammonia, but the genes encoding the other transporters have not been identified. Transport of several other solutes, including calcium and potassium, have been demonstrated in isolated symbiosomes, and genes encoding transport systems for the movement of iron, nitrate, sulfate, and zinc in nodules have been identified. However, definitively matching transport activities with these genes has proved difficult and many further transport processes are expected on the SM to facilitate the movement of nutrients between the symbionts. Recently, work detailing the SM proteome in soybean has been completed, contributing significantly to the database of known SM proteins. This represents a valuable resource for the identification of transporter protein candidates, some of which may correspond to transport processes previously described, or to novel transport systems in the symbiosis. Putative transporters identified from the proteome include homologs of transporters of sulfate, calcium, peptides, and various metal ions. Here we review current knowledge of transport processes of the SM and discuss the requirements for additional transport routes of other nutrients exchanged in the symbiosis, with a focus on transport systems identified through the soybean SM proteome.
format Online
Article
Text
id pubmed-4266029
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-42660292015-01-06 Transport processes of the legume symbiosome membrane Clarke, Victoria C. Loughlin, Patrick C. Day, David A. Smith, Penelope M. C. Front Plant Sci Plant Science The symbiosome membrane (SM) is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume:rhizobia symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is the transport of a carbon energy source from plant to bacteroid in exchange for fixed nitrogen. At a biochemical level two channels have been implicated in movement of fixed nitrogen across the SM and a uniporter that transports monovalent dicarboxylate ions has been characterized that would transport fixed carbon. The aquaporin NOD26 may provide a channel for ammonia, but the genes encoding the other transporters have not been identified. Transport of several other solutes, including calcium and potassium, have been demonstrated in isolated symbiosomes, and genes encoding transport systems for the movement of iron, nitrate, sulfate, and zinc in nodules have been identified. However, definitively matching transport activities with these genes has proved difficult and many further transport processes are expected on the SM to facilitate the movement of nutrients between the symbionts. Recently, work detailing the SM proteome in soybean has been completed, contributing significantly to the database of known SM proteins. This represents a valuable resource for the identification of transporter protein candidates, some of which may correspond to transport processes previously described, or to novel transport systems in the symbiosis. Putative transporters identified from the proteome include homologs of transporters of sulfate, calcium, peptides, and various metal ions. Here we review current knowledge of transport processes of the SM and discuss the requirements for additional transport routes of other nutrients exchanged in the symbiosis, with a focus on transport systems identified through the soybean SM proteome. Frontiers Media S.A. 2014-12-15 /pmc/articles/PMC4266029/ /pubmed/25566274 http://dx.doi.org/10.3389/fpls.2014.00699 Text en Copyright © 2014 Clarke, Loughlin, Day and Smith. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Plant Science
Clarke, Victoria C.
Loughlin, Patrick C.
Day, David A.
Smith, Penelope M. C.
Transport processes of the legume symbiosome membrane
title Transport processes of the legume symbiosome membrane
title_full Transport processes of the legume symbiosome membrane
title_fullStr Transport processes of the legume symbiosome membrane
title_full_unstemmed Transport processes of the legume symbiosome membrane
title_short Transport processes of the legume symbiosome membrane
title_sort transport processes of the legume symbiosome membrane
topic Plant Science
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4266029/
https://www.ncbi.nlm.nih.gov/pubmed/25566274
http://dx.doi.org/10.3389/fpls.2014.00699
work_keys_str_mv AT clarkevictoriac transportprocessesofthelegumesymbiosomemembrane
AT loughlinpatrickc transportprocessesofthelegumesymbiosomemembrane
AT daydavida transportprocessesofthelegumesymbiosomemembrane
AT smithpenelopemc transportprocessesofthelegumesymbiosomemembrane