Cooperation of tyrosine kinases p72syk and p53/56lyn regulates calcium mobilization in chicken B cell oxidant stress signaling.
A chicken B cell line DT40 and its syk-negative or lyn-negative mutants were used to investigate the roles of protein-tyrosine kinases in oxidant stress signaling. The data presented here for wild-type cells demonstrate that hydrogen peroxide stimulates p53/56lyn-dependent tyrosine phosphorylation and activation of p72syk, and induces a rapid and prolonged elevation of intracellular calcium, which consists of calcium release from intracellular stores and influx from the extracellular space. Hydrogen-peroxide-triggered calcium mobilization was impaired in both syk-negative and lyn-negative cells, which was mainly due to the loss of calcium release from intracellular stores. Further studies indicated that inositol trisphosphate production was also abolished in both syk-negative and lyn-negative cells, which is consistent with the loss of calcium release. Taken together, these observations suggest that the defect of p72syk or p53/56lyn was responsible for the abnormality of calcium mobilization in both lyn-negative and syk-negative cells, and that both p72syk and p53/56lyn might regulate calcium mobilization through the phosphatidylinositol pathway in B cell oxidant stress signaling.
Qin
S
S
Department of Biochemistry, Fukui Medical School, Matsuoka, Japan.
Inazu
T
T
Takata
M
M
Kurosaki
T
T
Homma
Y
Y
Yamamura
H
H
D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D002645:Chickens; D004792:Enzyme Precursors / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D010084:Oxidation-Reduction; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction; D013312:Stress, Physiological / Q000378:metabolism; D000072377:Syk Kinase; D019061:src-Family Kinases / Q000378:metabolism*
D004792:Enzyme Precursors; D047908:Intracellular Signaling Peptides and Proteins; D015544:Inositol 1,4,5-Trisphosphate; D006861:Hydrogen Peroxide; D011505:Protein-Tyrosine Kinases; D000072377:Syk Kinase; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases; D002118:Calcium