Sab Background Information Sab is a Src homology 3 domain (SH3) binding protein that preferentially associates with Bruton’s tyrosine kinase, Btk, over other related tyrosine kinases. Btk, together with Itk, Tec, Txk and Bmx, is a member of a family of cytoplasmic tyrosine kinases (the Btk/Tec family). Btk is a B cell specific kinase that is crucial for human and murine B cell development, and its deficiency causes human X-linked agammaglobulinemia and murine X-linked immunodeficiency. Sab serves as a negative regulator of Btk kinase activity and Sab binding to Btk reduces the phosphorylation of Btk substrates and also inhibits Btk-induced auto-phosphorylation in B cells. The SH3 domain of Sab directly binds to the SH3 domain of Btk and this interaction is essential for the reg-ulatory activity of Sab. Sab is more broadly expressed than Btk, suggesting that Sab may target additional protein kinases that are specific to various tissues.
Sab (PL-A23)
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Sab (PL-A23): sc-135617. Western blot analysis of Sab expression in non-transfected 293T: sc-117752 (A), human Sab transfected 293T: sc-171068 (B) and Raji (C) whole cell lysates.
Sab (PL-A23): sc-135617. Immunofluorescence staining of methanol-fixed HeLa cells showing nuclear localization.
Sab (PL-A23): sc-135617. Immunoperoxidase staining of formalin-fixed, paraffin-embedded human colon adenocarcinoma tissue showing cytoplasmic localization.
Sab (PL-A23): sc-135617. Western blot analysis of Sab expression in A-431 whole cell lysate.
