HYAL2(hyaluronoglucosaminidase 2) also known as hyaluronidase 2, LuCa-2, is an enzyme that in humans is encoded by the HYAL2 gene. HYAL2 cDNAs encode a preprotein with an N-terminal signal peptide. Northern blot analysis indicated that HYAL2 was expressed in all human tissues tested except adult brain, and Western blot analysis detected Hyal2protein in all mouse tissues examined except adult brain. The HYAL2 gene is mapped on 3p21.31. HYAL2 is a glycosylphosphatidylinositol (GPI)-anchored protein on the cell surface and serves as a receptor for entry into the cell of the jaagsiekte sheep retrovirus (JSRV). The findings of Rai et al. (2001) that HYAL2 is a GPI-anchored protein on the cell surface showed that GFP would likely be cleaved from HYAL2 during GPI addition, leaving HYAL2 on the cell surface and resulting in GFP transit to the lysosome for degradation.