Capsid is an important determinant for functional complementation of murine leukemia virus and spleen necrosis virus Gag proteins.
In this report, we examined the abilities and requirements of heterologous Gag proteins to functionally complement each other to support viral replication. Two distantly related gammaretroviruses, murine leukemia virus (MLV) and spleen necrosis virus (SNV), were used as a model system because SNV proteins can support MLV vector replication. Using chimeric or mutant Gag proteins that could not efficiently support MLV vector replication, we determined that a homologous capsid (CA) domain was necessary for the functional complementation of MLV and SNV Gag proteins. Findings from the bimolecular fluorescence complementation assay revealed that MLV and SNV Gag proteins were capable of colocalizing and interacting in cells. Taken together, our results indicated that MLV and SNV Gag proteins can interact in cells; however, a homologous CA domain is needed for functional complementation of MLV and SNV Gag proteins to complete virus replication. This requirement of homologous Gag most likely occurs at a postassembly step(s) of the viral replication.
Lee
Sook-Kyung
SK
HIV Drug Resistance Program, National Cancer Institute, Frederick, MD 21702, USA.
Boyko
Vitaly
V
Hu
Wei-Shau
WS
D000818:Animals; D036022:Capsid Proteins / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D002477:Cells / Q000737:chemistry; D004285:Dogs; D015683:Gene Products, gag / Q000378:metabolism / Q000502:physiology*; D005816:Genetic Complementation Test; D006801:Humans; D009052:Leukemia Virus, Murine / Q000502:physiology*; D018613:Microscopy, Confocal; D017434:Protein Structure, Tertiary; D053079:Trager duck spleen necrosis virus / Q000502:physiology*; D014779:Virus Replication
D036022:Capsid Proteins; D015683:Gene Products, gag