TABLE 1.
KSHV genes with immune modulatory functions
| KSHV protein |
KSHV gene |
Features and functions | Related proteins from other viruses |
|---|---|---|---|
| vKCP | ORF4 | Homolog of cellular complement control regulators; inhibits C3 deposition on cell surface |
HVS-ORF4, HSVl-gC, Vaccinia-vCP/C21L, Cowpox-IMP, Vaccinia-SPICE |
| KIS | ORFK1 | Constitutively active membrane protein containing ITAM motif; interacts with mu chains of B cell receptor complex to block surface transport; transforms rodent fibroblasts and primary T cells; activates Syk signaling pathway; variable ectodomain used for KSHV strain analysis |
HVS-STP |
| MIR1/MIR2 | ORFK3/K5 | Enhanced endocytosis of surface MHO via ubiquitination; MIR2 also ubiquitinates and downregulates ICAM-1 and B7.2 |
MHV 68-K3, CMV-US2 |
| vCCL-2 (vMIP-II) |
ORFK4 | Binds to CCR3 and induces angiogenesis in ovo; induces eosinophil and Th2 chemotaxis; CCR8 and vGPCR antagonist. |
Molluscum-MC148 |
| vCCL-3 (vMIP-III) |
ORFK4.1 | Agonist for CCR4 and induces Th2 chemotaxis; induces angiogenesis in ovo; protein expressed in KS lesions (by Western blot) |
|
| vCCL-1 (vMIP-I) |
ORFK6 | Bids CCR5 and induces angiogenesis in ovo; CCR8 agonist; induces Th2 chemotaxis |
Molluscum-MC148 |
| vIRF-1 | ORFK9 | Inhibits IFN signaling; binds CBP/p300; transforms rodent fibroblasts; protein expressed in MCD and PEL cell lines, not detectable in KS or PEL |
EBV-EBNA2, Adeno-EIA, EBV-EBNA2, Adeno-EIA, SV40-LT, HTLV-Tax |
| vFLIP | ORFK13 | Homolog of cellular apoptosis inhibitor (FLIP); transcribed on major latency transcripts (LT)1 and LT2; posttranscriptional regulation of protein expression in vivo |
HSV-ORF71 |
| ORF45 | ORF45 | Binds to and inhibits IRF7 nuclear translocation | Vaccinia-E3L |