Jump to main content
US EPA
United States Environmental Protection Agency
Search
Search
Main menu
Environmental Topics
Laws & Regulations
About EPA
Health & Environmental Research Online (HERO)
Contact Us
Print
Feedback
Export to File
Search:
This record has one attached file:
Add More Files
Attach File(s):
Display Name for File*:
Save
Citation
Tags
HERO ID
2985621
Reference Type
Journal Article
Title
Cloning and characterization of the OsNramp family from Oryza sativa, a new family of membrane proteins possibly implicated in the transport of metal ions
Author(s)
Belouchi, A; Kwan, T; Gros, P
Year
1997
Is Peer Reviewed?
1
Journal
Plant Molecular Biology
ISSN:
0167-4412
EISSN:
1573-5028
Volume
33
Issue
6
Page Numbers
1085-1092
Language
English
PMID
9154989
DOI
10.1023/A:1005723304911
Web of Science Id
WOS:A1997WZ47300013
Abstract
The mammalian Nramp1 protein is an integral membrane protein expressed exclusively in macrophages, where it plays a critical role in the ability of these cells to destroy ingested microbes. The bactericidal mechanism of action of Nramp1 remains unknown. We report the identification and characterization of cDNA clones corresponding to three homologues of the mammalian Nramp1 gene from the genome of Oryza sativa, OsNramp1, OsNramp2, and OsNramp3. These three genes encode a novel group of highly similar hydrophobic polypeptides sharing between 64% and 75% sequence similarity, that show similar hydropathy profiles, and predicted secondary structure, including the same number, position, and sequence characteristics (including conserved charges) of transmembrane domains. Together, these define a highly conserved membrane associated hydrophobic core. The three plant proteins show a remarkable degree of sequence similarity with their mammalian counterpart (60% to 70% similarity), including primary and secondary structure elements previously described in ion transporters and channels. Expression studies in normal plant tissues indicate that while OsNramp1 is expressed primarily in roots, and OsNramp2 is primarily expressed in leaves, OsNramp3 is expressed in both tissues. The recent discovery that the yeast Nramp homologue SMF1 functions as a manganese transporter raises the exciting possibility that OsNramp encodes a family of metal ion transporters in plants.
Home
Learn about HERO
Using HERO
Search HERO
Projects in HERO
Risk Assessment
Transparency & Integrity