当前位置： SCI文献检索 > VIROLOGY期刊下所有文献 > Isoprenylation of large hepatitis delta antigen is necessary but not sufficient for hepatitis delta virus assembly.

Isoprenylation of large hepatitis delta antigen is necessary but not sufficient for hepatitis delta virus assembly.

Abstract：

:Hepatitis delta virus (HDV) encodes two proteins, the small hepatitis delta antigen (SHDAg) and large hepatitis delta antigen (LHDAg). Both proteins are identical except for the presence of additional 19 amino acids at the C terminus of LHDAg. While SHDAg is required for HDV RNA replication, LHDAg inhibits replication and is required together with hepatitis B surface antigen for the assembly of HDV. The C-terminal last 4 amino acids of LHDAg (Cys-Arg-Pro-Gln) is an isoprenylation motif. It has previously been shown that the mutation of the Cys inhibited the assembly of HDV. In order to discern whether this effect is due to change of amino acid residue or abolition of isoprenylation, we constructed several LHDAg mutants of the terminal three amino acid residues and tested their abilities to be packaged with HBsAg by cotransfection experiments. We also made GST-fusion proteins of these mutants and tested their abilities to be isoprenylated in rabbit reticulocyte lysate system. We found that some, but not all, of the substitutions of the amino acid residues other than the Cys also inhibited isoprenylation and that the status of isoprenylation of these mutant proteins correlated well with their abilities to be packaged with HBsAg into virions. This result indicates that isoprenylation, rather than the primary amino acid sequence, is required for LHDAg packaging. Furthermore, we found that the attachment of an isoprenylation motif to SHDAg did not enable it to be packaged with HBsAg and that the deletions of any 5 amino acids in the last 15 amino acids (amino acids 196 to 210) unique to the LHDAg abolished the packaging ability. In contrast, the deletion of 33 amino acids (amino acids 163 to 195) upstream of the last C-terminal 19 amino acids of LHDAg did not interfere with its packaging ability. Therefore, we conclude that the 15 amino acids upstream of the isoprenylation site of LHDAg are also essential for HDV assembly, and a large portion of the alleged C-terminal Pro/Gly-rich region (amino acids 146 to 195) is not required for the assembly process.

journal_name

Virology

journal_title

Virology

authors

Lee CZ,Chen PJ,Lai MM,Chen DS

doi

10.1006/viro.1994.1109

subject

Has Abstract

pub_date

1994-02-15 00:00:00

pages

169-75

issue

eissn

0042-6822

issn

1096-0341

pii

S0042682284711093

journal_volume

199

pub_type

杂志文章

在线工具

Isoprenylation of large hepatitis delta antigen is necessary but not sufficient for hepatitis delta virus assembly.