Essential Role of Domain III of Nonstructural Protein 5A for Hepatitis C Virus Infectious Particle Assembly

نویسندگان

  • Nicole Appel
  • Margarita Zayas
  • Sven Miller
  • Jacomine Krijnse-Locker
  • Torsten Schaller
  • Peter Friebe
  • Stephanie Kallis
  • Ulrike Engel
  • Ralf Bartenschlager
چکیده

Persistent infection with the hepatitis C virus (HCV) is a major risk factor for the development of liver cirrhosis and hepatocellular carcinoma. With an estimated about 3% of the world population infected with this virus, the lack of a prophylactic vaccine and a selective therapy, chronic hepatitis C currently is a main indication for liver transplantation. The establishment of cell-based replication and virus production systems has led to first insights into the functions of HCV proteins. However, the role of nonstructural protein 5A (NS5A) in the viral replication cycle is so far not known. NS5A is a membrane-associated RNA-binding protein assumed to be involved in HCV RNA replication. Its numerous interactions with the host cell suggest that NS5A is also an important determinant for pathogenesis and persistence. In this study we show that NS5A is a key factor for the assembly of infectious HCV particles. We specifically identify the C-terminal domain III as the primary determinant in NS5A for particle formation. We show that both core and NS5A colocalize on the surface of lipid droplets, a proposed site for HCV particle assembly. Deletions in domain III of NS5A disrupting this colocalization abrogate infectious particle formation and lead to an enhanced accumulation of core protein on the surface of lipid droplets. Finally, we show that mutations in NS5A causing an assembly defect can be rescued by trans-complementation. These data provide novel insights into the production of infectious HCV and identify NS5A as a major determinant for HCV assembly. Since domain III of NS5A is one of the most variable regions in the HCV genome, the results suggest that viral isolates may differ in their level of virion production and thus in their level of fitness and pathogenesis.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Coordination of Hepatitis C Virus Assembly by Distinct Regulatory Regions in Nonstructural Protein 5A

Hepatitis C virus (HCV) nonstructural protein (NS)5A is a RNA-binding protein composed of a N-terminal membrane anchor, a structured domain I (DI) and two intrinsically disordered domains (DII and DIII) interacting with viral and cellular proteins. While DI and DII are essential for RNA replication, DIII is required for assembly. How these processes are orchestrated by NS5A is poorly understood...

متن کامل

Apolipoprotein E interacts with hepatitis C virus nonstructural protein 5A and determines assembly of infectious particles.

UNLABELLED Chronic hepatitis C virus (HCV) infection is a major cause of liver disease worldwide. Restriction of HCV infection to human hepatocytes suggests that liver-specific host factors play a role in the viral life cycle. Using a yeast-two-hybrid system, we identified apolipoprotein E (apoE) as a liver-derived host factor specifically interacting with HCV nonstructural protein 5A (NS5A) bu...

متن کامل

The lysine methyltransferase SMYD3 interacts with hepatitis C virus NS5A and is a negative regulator of viral particle production

Hepatitis C virus (HCV) is a considerable global health and economic burden. The HCV nonstructural protein (NS) 5A is essential for the viral life cycle. The ability of NS5A to interact with different host and viral proteins allow it to manipulate cellular pathways and regulate viral processes, including RNA replication and virus particle assembly. As part of a proteomic screen, we identified s...

متن کامل

Interaction of hepatitis C virus nonstructural protein 5A with core protein is critical for the production of infectious virus particles.

Nonstructural protein 5A (NS5A) of the hepatitis C virus (HCV) possesses multiple and diverse functions in RNA replication, interferon resistance, and viral pathogenesis. Recent studies suggest that NS5A is involved in the assembly and maturation of infectious viral particles; however, precisely how NS5A participates in virus production has not been fully elucidated. In the present study, we de...

متن کامل

Trafficking of Hepatitis C Virus Core Protein during Virus Particle Assembly

Hepatitis C virus (HCV) core protein is directed to the surface of lipid droplets (LD), a step that is essential for infectious virus production. However, the process by which core is recruited from LD into nascent virus particles is not well understood. To investigate the kinetics of core trafficking, we developed methods to image functional core protein in live, virus-producing cells. During ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • PLoS Pathogens

دوره 4  شماره 

صفحات  -

تاریخ انتشار 2008