Functional selectivity for glycerol of the nodulin 26 subfamily of plant membrane intrinsic proteins

FEBS Letters

Roberts, Daniel M¹  Wills, David M¹  Guenther, James F¹  Wallace, Ian S¹ 

[1] Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN 37996, USA

关键词: Aquaporin;    Major intrinsic protein family;    Nitrogen fixation;   

DOI  :  10.1016/S0014-5793(02)02955-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The nodulin-like intrinsic protein (NIP) subfamily of water and solute channels in plants is named for nodulin 26 of legume nodules. Two NIPs, soybean nodulin 26 and Lotus japonicus LIMP2, show a distinct functional profile with a low intrinsic osmotic water permeability (P _f) and the ability to flux uncharged polyols such as glycerol. NIPs have a conserved signature sequence within the ‘aromatic/arginine’ region that forms the selectivity filter for major intrinsic proteins. This sequence is a hybrid of glyceroporin and aquaporin residues as well as exhibiting substitutions unique to the NIP subfamily. Site-directed mutagenesis of a conserved tryptophan in helix 2 of LIMP2 shows that this is a major determinant of glycerol selectivity.

【 授权许可】

Unknown