%0 Journal Article
%T The unsulfated extracellular N-terminus of vGPCR reduces the tumorigenicity of hGRO-¦Á in nude mice
%A Hui Wu
%A YongMing Fu
%A Jun Xiao
%A Man Zhou
%A Wei Zhou
%A Hao Feng
%J Science China Life Sciences
%@ 1869-1889
%D 2013
%I 
%R 10.1007/s11427-012-4405-9
%X The Kaposi¡¯s Sarcoma-associated Herpesvirus (KSHV)-encoded G-protein coupled receptor (vGPCR) is an oncoprotein that is implicated in KSHV-associated malignancies. We previously revealed vGPCR incorporates sulfate groups within its extracellular N-terminal tyrosine residues (Y26 and Y28) and that this tyrosine sulfation is crucial for its tumorigenicity in nude mice. hGRO-¦Á binds vGPCR in a sulfotyrosine-dependent manner and promotes its tumorigenicity through autocrine signaling. Interestingly, an unsulfated vGPCR mutant (yydd-vGPCR) attenuated the tumor growth triggered by hGRO-¦Á. In this study, the extracellular N-terminus of vGPCR (wt-vGN) and an unsulfated vGPCR mutant (yydd-vGN) were individually secreted, expressed and purified. A radioactive labeling assay demonstrated that wt-vGN but not yydd-vGN incorporated [35S]-sulfate. In nude mice, NIH3T3 cells expressing yydd-vGN but not wt-vGN could significantly inhibit the tumor growth triggered by hGRO-¦Á. All our data support the conclusion that the unsulfated extracellular N-terminus of vGPCR reduces the tumorigenicity of hGRO-¦Á.
%K KSHV
%K vGPCR
%K hGRO-¦Á
%K sulfotyrosine
%K tumorigenicity
%U http://link.springer.com/article/10.1007/s11427-012-4405-9