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Nucleophosmin phosphorylation by v-cyclin-CDK6 controls KSHV latency.
Grzegorz Sarek1, Annika Järviluoma, Henna M Moore
1Genome-Scale Biology Program, Biomedicum Helsinki & Institute of Biomedicine, University of Helsinki, Helsinki, Finland.
Plos Pathogens
|March 25, 2010
Summary
Kaposi's sarcoma herpesvirus (KSHV) v-cyclin phosphorylates nucleophosmin (NPM), a protein crucial for maintaining KSHV latency. NPM's phosphorylation by v-cyclin and CDK6 regulates KSHV infection states.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Nucleophosmin (NPM) is a nuclear phosphoprotein involved in chromatin organization and transcription.
- Kaposi's sarcoma herpesvirus (KSHV) causes Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman disease.
- KSHV infection involves latency and productive replication phases, critical for viral persistence and pathogenesis.
Purpose of the Study:
- To investigate the role of NPM in KSHV infection.
- To determine how KSHV manipulates NPM function.
- To elucidate the mechanism regulating KSHV latency.
Main Methods:
- Phosphorylation site analysis of NPM in KSHV-infected cells and tumors.
- Investigating the interaction between NPM, v-cyclin, and LANA.
- Depletion of NPM in PEL cells to assess viral reactivation.
Main Results:
- KSHV v-cyclin and CDK6 phosphorylate NPM on threonine 199 (Thr199).
- NPM phosphorylation by v-cyclin promotes interaction with LANA, a KSHV latency-associated protein.
- NPM depletion triggers KSHV reactivation and viral production.
- NPM phosphorylation inversely correlates with KSHV reactivation levels.
Conclusions:
- NPM is a key regulator of KSHV latency.
- NPM's interaction with v-cyclin and LANA controls KSHV infection states.
- Targeting NPM phosphorylation may offer therapeutic strategies for KSHV-associated diseases.
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