An N-terminal glycine-rich sequence contributes to retrovirus trimer of hairpins stability

作者：Wilson Kirilee A; Maerz Anne L; Bar Serverine; Drummer Heidi E; Poumbourios Pantelis^*

来源：Biochemical and Biophysical Research Communications, 2007, 359(4): 1037-1043.

DOI：10.1016/j.bbrc.2007.06.011

• retrovirus
• transmembrane glycoprotein
• hairpin
• biochemical analysis
• membrane fusion

Retroviral transmembrane proteins (TMs) contain a glycine-rich segment linking the N-terminal fusion peptide and coiled coil core. Previously, we reported that the glycine-rich segment (Met-326-Ser-337) of the human T-cell leukemia virus type I (HTLV-1) TM, gp21, is a determinant of membrane fusion function [K.A. Wilson, S. Bar, A.L. Maerz, M. Alizon, P. Poumbourios, The conserved glycine-rich segment linking the N-terminal fusion peptide to the coiled coil of human T-cell leukemia virus type I transmembrane glycoprotein gp21 is a determinant of membrane fusion function, J. Virol. 79 (2005) 4533-4539]. Here we show that the reduced fusion activity of an I334A mutant correlated with a decrease in stability of the gp21 trimer of hairpins conformation, in the context of a maltose-binding protein-gp21 chimera. The stabilizing influence of Ile-334 required the C-terminal membrane-proximal sequence Trp-431-Ser-436. Proline substitution of four of five Gly residues altered gp21 trimer of hairpins stability. Our data indicate that flexibility within and hydrophobic interactions mediated by this region are determinants of gp21 stability and membrane fusion function.

• 出版日期2007-8-10
• 单位河北医科大学