"We have examined whether the other two members of the Raf family, A-Raf and B-Raf, are regulated in a similar way to Raf-1. A-Raf behaves like Raf-1, being weakly activated by oncogenic Ras more strongly activated by oncogenic Src, and these signals synergize to give maximal activation. B-Raf by contrast is strongly activated by oncogenic Ras alone and is not activated by oncogenic Src."
"The first RAS effector pathway to be identified was the RAF-MEK-ERK pathway. This pathway is an essential, shared element of mitogenic signaling involving tyrosine kinase receptors, leading to a wide range of cellular responses, including growth, differentiation, inflammation, and apoptosis.23 The RAF family of proteins (Raf-1, A-Raf, and B-Raf) is serine/threonine kinases that bind to the effector region of RAS-GTP, thus inducing translocation of the protein to the plasma membrane."