The C-terminal helical domain of dengue virus precursor membrane protein is involved in virus assembly and entry.
The role of the α-helical domain (MH) of dengue virus (DENV) precursor membrane protein in replication was investigated by site-directed mutagenesis. Proline substitutions of three residues (120, 123 and 127) at the C-terminus, but not those at the N-terminus of MH domain, reduced the virus-like particles of DENV1, DENV2 and DENV4 detected in supernatants. In a DENV2 replicon trans-packaging system, these three mutations suppressed particles detected; two of them (I123P and V127P) also affected viral entry. In the context of DENV2 genome-length RNA, all three mutations reduced virion assembly and virus spreading in cell culture. Analysis of revertants showed that mutation A120P could partially support viral infection cycle; in contrast, mutations I123P and V127P were lethal, and adaptations of I123P→I123L and V127P→V127L were required to restore the viral infection cycle. These findings demonstrate that the C-terminus of the MH domain is involved in both assembly and entry of DENV.
Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan.
Szu-Chia
SC
Hsieh
Gang
G
Zou
Wen-Yang
WY
Tsai
Min
M
Qing
Gwong-Jen
GJ
Chang
Pei-Yong
PY
Shi
Wei-Kung
WK
Wang
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D003716:Dengue Virus / Q000235:genetics / Q000378:metabolism*; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D006801:Humans; D051379:Mice; D009154:Mutation; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019065:Virus Assembly / Q000502:physiology*; D053586:Virus Internalization
D011498:Protein Precursors; D014763:Viral Matrix Proteins