An engineered mutant of a host phospholipid synthesis gene inhibits viral replication without compromising host fitness

• Published in: The Journal of biological chemistry Vol. 294; no. 38; pp. 13973 - 13982
• Main Authors: He, Guijuan, Zhang, Zhenlu, Sathanantham, Preethi, Zhang, Xin, Wu, Zujian, Xie, Lianhui, Wang, Xiaofeng
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20.09.2019; American Society for Biochemistry and Molecular Biology
• Subjects: Bromovirus - metabolism; Endoplasmic Reticulum - metabolism; Genetic Engineering - methods; metabolic engineering; Microbiology; phosphatidylcholine; Phosphatidylcholines - metabolism; phosphatidylethanolamine methyltransferase; Phosphatidylethanolamine N-Methyltransferase - genetics; Phosphatidylethanolamine N-Methyltransferase - metabolism; Phospholipids - genetics; Phospholipids - metabolism; plus-stranded RNA virus; protein targeting; RNA, Viral - metabolism; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; Viral Proteins - metabolism; viral replication; viral replication complex; virus control; Virus Replication - genetics; viral replication; viral replication complex; phosphatidylcholine; plus-stranded RNA virus; protein targeting; metabolic engineering; phosphatidylethanolamine methyltransferase; virus control
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.RA118.007051

Viral infections universally rely on numerous hijacked host factors to be successful. It is therefore possible to control viral infections by manipulating host factors that are critical for viral replication. Given that host genes may play essential roles in certain cellular processes, any successful manipulations for virus control should cause no or mild effects on host fitness. We previously showed that a group of positive-strand RNA viruses enrich phosphatidylcholine (PC) at the sites of viral replication. Specifically, brome mosaic virus (BMV) replication protein 1a interacts with and recruits a PC synthesis enzyme, phosphatidylethanolamine methyltransferase, Cho2p, to the viral replication sites that are assembled on the perinuclear endoplasmic reticulum (ER) membrane. Deletion of the CHO2 gene inhibited BMV replication by 5-fold; however, it slowed down host cell growth as well. Here, we show that an engineered Cho2p mutant supports general PC synthesis and normal cell growth but blocks BMV replication. This mutant interacts and colocalizes with BMV 1a but prevents BMV 1a from localizing to the perinuclear ER membrane. The mislocalized BMV 1a fails to induce the formation of viral replication complexes. Our study demonstrates an effective antiviral strategy in which a host lipid synthesis gene is engineered to control viral replication without comprising host growth.