When does BTK Brutons tyrosine kinase become active in Bcell

When does BTK (Bruton\'s tyrosine kinase) become active in B-cell development?

Solution

Answer:

Bruton\'s tyrosine kinase plays role in activation of B cells and mast cells. To the PH domain of Bruton\'s tyrosine kinase, phosphatidylinositol (3,4,5)-trisphosphate (PIP3) binds.

Due to binding of PIP3 to PH domain, phospholipase C is phosphorylated, which further hydrolysed phosphatidylinositol (PIP2) into diacylglycerol (DAG) and inositol triphosphate (IP3) which enhances development of B Cell. Both are secondary messenger (IP3 and DAG). By this pathway , B-cell development takes place.