hrp

Protein A is surface protein originally found in the cell wall of the bacteria Staphylococcusaureus. It is encoded by the spa gene and its regulation is controlled by DNA topology, cellular osmolarity, and a two component system called ArlS-ArlR. Protein A binds the Fc region of various mammalian IgG subclasses including: Human IgG1, IgG2, IgG3 (weakly), IgG4 Mouse IgG1 (weakly), IgG2a, IgG2b, IgG3 SPA also binds IgG from monkey, rabbit, pig, guinea pig, dog, rat and cat. It also weakly binds to streptavidin.

Unlike some other CBS-domain containing proteins does not seem to bind AMP.

Hepatoma-Derived Growth Factor-Related Protein 3 (HDGFRP3) belongs to the HDGF family. HDGFRP3 can be found in testis, heart, spinal cord and brain. HDGFRP3 localizes to the nucleus and contains one PWWP domain. HDGFRP3 enhances DNA synthesis and may have a role in cell proliferation.