Lenz O, ter Meulen J, Feldmann H, Klenk H D, Garten W
Institut für Virologie, D-35037 Marburg, Germany.
J Virol. 2000 Dec;74(23):11418-21. doi: 10.1128/jvi.74.23.11418-11421.2000.
The Lassa virus glycoprotein consists of an amino-terminal and a carboxy-terminal cleavage fragment designated GP-1 and GP-2, respectively, that are derived by proteolysis from the precursor GP-C. The membrane-anchored GP-2 obtained from purified virions of the Josiah strain revealed the N-terminal tripeptide GTF(262) when analyzed by Edman degradation. Upstream of this site, GP-C contains the tetrapeptide sequence RRLL(259), which is conserved in all Lassa virus isolates published to date. Systematic mutational analysis of vector-expressed GP-C revealed that the motif R-X (L/I/V)-L(259) (where X stands for L, I, or V) is essential for cleavage of the peptide bond between leucine(259) and glycine(260). This cleavage motif is homologous to the consensus sequence recognized by a novel class of cellular endoproteases which have so far not been implicated in the processing of viral glycoproteins.
拉沙病毒糖蛋白由分别命名为GP-1和GP-2的氨基末端和羧基末端裂解片段组成，它们通过蛋白酶解从前体GP-C衍生而来。通过埃氏降解法分析从约西亚毒株纯化病毒粒子获得的膜锚定GP-2时，发现其N端三肽为GTF(262)。在此位点上游，GP-C含有四肽序列RRLL(259)，该序列在迄今公布的所有拉沙病毒分离株中均保守。对载体表达的GP-C进行系统突变分析表明，基序R-X (L/I/V)-L(259)（其中X代表L、I或V）对于亮氨酸(259)和甘氨酸(260)之间肽键的裂解至关重要。这种裂解基序与一类新型细胞内蛋白酶识别的共有序列同源，这类蛋白酶迄今尚未涉及病毒糖蛋白的加工过程。
