SH3 domain-binding protein 5 (SH3BP5)

SH3 domain-binding protein 5 (SH3BP5) is a cytoplasmic signaling protein primarily recognized for its roles as a guanine nucleotide exchange factor (GEF) for Rab11 subfamily members (Rab11A, Rab11B, Rab25), crucial in endosomal recycling and trafficking[1][4][7]. SH3BP5 is also known as SAB or SH3BP-5 and is notable for its protein-protein interactions, particularly with Bruton's tyrosine kinase (BTK), where it acts as a negative regulator by inhibiting BTK autophosphorylation and subsequent signaling in B cells[1][2][8]. SH3BP5 influences intracellular signal transduction, protein kinase inhibition, and apoptotic pathways in immune cells. Impaired BTK regulation via SH3BP5 has clinical relevance in hematologic cancers and X-linked agammaglobulinemia. Although SH3BP5 is a functional mediator in key cellular and disease processes, no drugs directly targeting this protein are currently in use, and it is not employed as a biomarker or direct therapeutic target in routine clinical practice[8].

Other names

SABSH3BP-5SabSH3 domain-binding protein that preferentially associates with BTKSH3 binding proteinSH3-domain binding protein 5 (BTK-associated)

Not applicable: no direct pharmacological agents known to target SH3BP5. Drug mechanisms derived from its regulatory role (e.g., modulation of BTK signaling indirectly affects BTK inhibitor efficacy)