Palmitylation of Src family tyrosine kinases regulates functional interaction with a B cell substrate.
Palmitylation of Src family tyrosine kinases has been shown to play a role in directing their membrane localization. Here we demonstrate that palmitylation can also regulate recognition and tyrosine phosphorylation of the B cell Src kinase substrate Ig alpha. Blk and Src, which are not palmitylated, phosphorylate co-expressed Ig alpha in Cos cells, whereas palmitylated Src kinases do not. Addition of a palmitylation site to Blk abrogates its phosphorylation of the substrate, while mutation of Fyn's palmitylation sites results in recognition and phosphorylation of Ig alpha. These results indicate that palmitylation, a reversible protein modification, aids in regulating recognition of physiologic substrates by Src family tyrosine kinases.
Saouaf
S J
SJ
Department of Oncology, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, New Jersey 08543, USA.
Wolven
A
A
Resh
M D
MD
Bolen
J B
JB
D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000737:chemistry / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D051925:CD79 Antigens; D019556:COS Cells; D016297:Mutagenesis, Site-Directed; D010169:Palmitic Acids / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D011947:Receptors, Antigen, B-Cell / Q000737:chemistry / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013379:Substrate Specificity; D014162:Transfection; D019061:src-Family Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D015703:Antigens, CD; D051925:CD79 Antigens; D010169:Palmitic Acids; D011518:Proto-Oncogene Proteins; D011947:Receptors, Antigen, B-Cell; D011993:Recombinant Fusion Proteins; D051076:Proto-Oncogene Proteins c-fyn; D019061:src-Family Kinases