Human cytomegalovirus pp71: a new viral tool to probe the mechanisms of cell cycle progression and oncogenesis controlled by the retinoblastoma family of tumor suppressors.

Retinoblastoma Family of Tumor Proteasome-Dependent Degradation of the Cell Cycle Progression by Inducing the Human Cytomegalovirus pp71 Stimulates

Proteasome-dependent, ubiquitin-independent degradation of the Rb family of tumor suppressors by the human cytomegalovirus pp71 protein.

Most of the substrates degraded by the proteasome are marked with polyubiquitin chains. However, there are a limited number of examples of nonubiquitinated proteins that are degraded by the proteasome. Here, we describe the degradation of the retinoblastoma family of tumor suppressor proteins by the proteasome in the absence of polyubiquitination. The retinoblastoma protein (p105), p107, and p1...

The retinoblastoma tumor suppressor promotes efficient human cytomegalovirus lytic replication.

UNLABELLED The retinoblastoma (Rb) tumor suppressor controls cell cycle, DNA damage, apoptotic, and metabolic pathways. DNA tumor virus oncoproteins reduce Rb function by either inducing Rb degradation or physically disrupting complexes between Rb and its myriad binding proteins. Human cytomegalovirus (HCMV), a betaherpesvirus being investigated for potential roles in human cancers, encodes mul...

Human T Lymphotropic Virus Type I (HTLV-I) Oncogenesis: Molecular Aspects of Virus and Host Interactions in Pathogenesis of Adult T cell Leukemia/Lymphoma (ATL)

    The study of tumor viruses paves the way for understanding the mechanisms of virus pathogenesis, including those involved in establishing infection and dissemination in the host tumor affecting immune-compromised patients. The processes ranging from viral infection to progressing malignancy are slow and usually insufficient for establishment of transformed cells that develop cancer in only ...

Interaction between the human cytomegalovirus UL82 gene product (pp71) and hDaxx regulates immediate-early gene expression and viral replication.

The human cytomegalovirus UL82-encoded pp71 protein is required for efficient virus replication and immediate-early gene expression when cells are infected at a low multiplicity. Functions attributed to pp71 include the ability to enhance the infectivity of viral DNA, bind to and target hypophosphorylated Rb family member proteins for degradation, drive quiescent cells into the cell cycle, and ...