Question

(1/3) Even though the GRB2 lacks intrinsic enzymatic activity, it is an essential component of the epidermal growth factor signaling pathway that activates MAP kinase. What is the function of GRB2? What role do Sh2 and Sh3 domains play in the function of GRB2?

Answer 1

GRB2 is an essential component of the EGF signaling pathway that activates MAP kinase. The SH2 and SH3 domains of GRB2 play crucial roles in its function.

Step-by-step explanation:

The function of GRB2 is to be an essential component of the epidermal growth factor (EGF) signaling pathway that activates MAP kinase. While GRB2 itself lacks intrinsic enzymatic activity, it plays a crucial role in activating downstream signaling cascades.

The SH2 (Src Homology 2) and SH3 (Src Homology 3) domains of GRB2 are important for its function. The SH2 domain allows GRB2 to bind to phosphorylated tyrosine residues on the activated EGF receptor, while the SH3 domain mediates interactions with other signaling molecules, such as SOS (Son of Sevenless). These interactions help to recruit and activate downstream components of the MAP kinase pathway.