Related Experiment Videos
[Evidence of protein kinase activity in 2 murine oncornaviruses]
Abstract:
A protein kinase activity has been detected in two strains of murine Oncornaviruses, MSV/MLV and EFV. This activity phosphorylates not only endogenous viral proteins but also exogenous substrates (histones and phosvitin). The stimulation of enzyme activity by detergents along with the increase of specific activity in viruses treated with trypsin during purification suggest that the enzyme is located in the viral particle.
Insights
Murine Oncornaviruses exhibit protein kinase activity, phosphorylating viral and exogenous proteins. This enzyme is likely located within the viral particle, as suggested by detergent stimulation and trypsin treatment during purification.
Area of Science:
- Virology
- Molecular Biology
- Biochemistry
Background:
- Murine Oncornaviruses are retroviruses known to cause tumors in mice.
- Protein kinases play crucial roles in cellular signaling and viral replication.
- The enzymatic activities of retroviral particles are not always fully characterized.
Purpose of the Study:
- To detect and characterize protein kinase activity in murine Oncornaviruses.
- To identify the substrates of this viral protein kinase.
- To determine the location of the protein kinase within the viral particle.
Main Methods:
- Detection of protein kinase activity in purified MSV/MLV and EFV viral strains.
- Assay of phosphorylation of endogenous viral proteins and exogenous substrates (histones, phosvitin).
- Analysis of enzyme activity modulation by detergents and trypsin treatment.
Main Results:
- Protein kinase activity was identified in both MSV/MLV and EFV.
- The kinase activity was shown to phosphorylate both endogenous viral proteins and exogenous substrates like histones and phosvitin.
- Enzyme activity increased with detergent treatment and after trypsin purification, indicating particle association.
Conclusions:
- Murine Oncornaviruses possess an intrinsic protein kinase activity.
- This viral protein kinase can phosphorylate a range of protein substrates.
- Evidence strongly suggests the protein kinase is an integral component of the viral particle.