Disease relevance of HHV8gp75

• In situ hybridization indicated that mRNAs for v-cyclin D and kaposin, an HHV-8 latency-associated gene, were present in approximately 1% of the spindle cells in early patch lesions and approximately 60% of the spindle cells in late nodular lesions of Kaposi's sarcoma [1].
• The KSHV miRNAs are expressed from what appears to be a single genetic locus that largely coincides with an approximately 4-kb noncoding sequence located between the KSHV v-cyclin and K12/Kaposin genes, both of which are also expressed in latently infected cells [2].
• All transformed Rat-3 cell lines containing kaposin sequences produced high-grade, highly vascular, undifferentiated sarcomas upon subcutaneous injection of athymic nu/nu mice [3].
• All of the ORFs present in KSHV have at least one homologue in RRV26-95 except K3 and K5 (bovine herpesvirus-4 immediate-early protein homologues), K7 (nut-1), and K12 (Kaposin) [4].

High impact information on HHV8gp75

• Identification of kaposin (open reading frame K12) as a human herpesvirus 8 (Kaposi's sarcoma-associated herpesvirus) transforming gene [3].
• Constructs with kaposin expressed either from its endogenous promoter or from a heterologous promoter induced focal transformation upon transfection into Rat-3 cells [3].
• Tumor-derived cell lines expressed kaposin mRNA, suggesting a role in the maintenance of the transformed phenotype [3].
• Definition of an optimal cytotoxic T lymphocyte epitope in the latently expressed Kaposi's sarcoma-associated herpesvirus kaposin protein [5].
• Kaposin A coding sequences were cloned into a eukaryotic expression plasmid with the Flag (FL) epitope fused in-frame at the C-terminus (Kap-FL) [6].

Biological context of HHV8gp75

• T0.7 encodes a unique HHV-8 open reading frame, K12, also known as kaposin [3].
• Sequence analysis of the genome and subsequent studies revealed several genes including kaposin, with transformation properties in cell culture [6].

Anatomical context of HHV8gp75

• More importantly, expression of kaposin protein was also detected in the PEL cell lines BCBL-1 and KS-1 [3].
• Although there was no staining at the cell membrane of transfected cells, FACS analysis using kap-2 or Flag antibodies, under nonpermeable conditions, showed positivity [7].

Analytical, diagnostic and therapeutic context of HHV8gp75

• Furthermore, kaposin protein was detected in transformed and tumor-derived cells by immunofluorescence and localized to the cytoplasm [3].
• Expression of kaposin protein was analyzed by Western blot analysis and indirect immunofluorescence assay (IFA) [8].
• DESIGN: The presence of kaposin DNA in transformed cells was determined by fluorescent in situ hybridization (FISH) [8].
• Because there is controversial data regarding the localization of Kaposin in cells, we examined the subcellular localization of Kaposin using confocal microscopy [7].

References