The Src-like adaptor protein 2 regulates colony-stimulating factor-1 receptor signaling and down-regulation.

Src-like adaptor protein 2 (SLAP-2) is a hematopoietic adaptor protein previously implicated as a negative regulator of T-cell antigen receptor (TCR)-mediated signaling. SLAP-2 contains an SH3 and an SH2 domain, followed by a unique carboxyl-terminal tail, which is important for c-Cbl binding. Here we describe a novel role for SLAP-2 in regulation of the colony-stimulating factor 1 receptor (CSF-1R), a receptor tyrosine kinase important for growth and differentiation of myeloid cells.

Threonines 2638/2647 in DNA-PK are essential for cellular resistance to ionizing radiation.

DNA-dependent protein kinase (DNA-PK) is required for the repair of double-stranded DNA breaks through the nonhomologous DNA end joining pathway. DNA-PK activity is required for DNA repair, but kinase activity also appears to be attenuated through an autoregulatory feedback loop. We show that autophosphorylation of DNA-PK catalytic subunit occurs in trans at least three sites NH(2) terminal to the catalytic domain and that two sites, threonine 2638 and 2647, determine DNA-PK autophosphorylation in vitro.