title: Identification and characterization of a novel gene encoding an RGD-containing protein in large yellow croaker iridovirus.
abstract: Many virus-encoded RGD-containing proteins have been reported to play important roles in virus attachment and entry. Here we report the identification and functional characterization of a gene encoding an RGD-containing protein (037L) from large yellow croaker iridovirus (LYCIV), a causative agent of epizootics among large yellow croaker, Pseudosciaena crocea. The 037L gene is 1347 bp long and encodes a protein of 449 amino acids containing a biologically active RGD tri-peptide predicted with SURFC and STRIDE software. Temporal analysis of 037L gene transcription showed that this gene was a late gene. Subcellular localization of 037L in insect Hi5 cells using baculovirus vector system indicated that 037L might be a membrane-tropistic protein and functionally associated with the cytoplasma-membrane. The recombinant 037L expressed in E. coli could effectively induce the morphological changes of BF-2 cells and promote cellular aggregation, demonstrating that it can bind with surface molecules of BF-2 cells. The neutralization assay showed that LYCIV infection of BF-2 cells was significantly inhibited by anti-037L IgG, as determined by a real-time PCR of viral concentrations in the culture supernatants of LYCIV-infected cells, suggesting that it might have an important role in virus infectivity. This is the first report of the functional gene involved in virus infection and virus-host interaction in Megalocytivirus.
authors.affiliation: Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, 178 Daxue Road, Xiamen 361005, PR China.
authors.forename: Jingqun
authors.initials: J
authors.lastname: Ao
authors.forename: Xinhua
authors.initials: X
authors.lastname: Chen
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D001483:Base Sequence; D002449:Cell Aggregation; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry; D020869:Gene Expression Profiling; D005814:Genes, Viral; D017994:Iridovirus / Q000235:genetics* / Q000276:immunology / Q000502:physiology; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D009842:Oligopeptides / Q000737:chemistry*; D010473:Perciformes; D011485:Protein Binding; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D053585:Virus Attachment; D053586:Virus Internalization
chemical_list: D000914:Antibodies, Viral; D009842:Oligopeptides; D012333:RNA, Messenger; D012367:RNA, Viral; D011994:Recombinant Proteins; D014764:Viral Proteins; C047981:arginyl-glycyl-aspartic acid