| First Author | Liu L | Year | 1994 |
| Journal | J Biol Chem | Volume | 269 |
| Issue | 24 | Pages | 16774-9 |
| PubMed ID | 7515884 | Mgi Jnum | J:18784 |
| Mgi Id | MGI:67019 | Doi | 10.1016/s0021-9258(19)89458-9 |
| Citation | Liu L, et al. (1994) Steel factor stimulates the serine/threonine phosphorylation of the interleukin-3 receptor. J Biol Chem 269(24):16774-9 |
| abstractText | The murine interleukin-3 (IL-3) dependent cell line, B6SUtA1, which expresses high IL-3 receptor (IL-3R) numbers, was found to proliferate in a greater than additive fashion when grown in the presence of IL-3 and steel factor (SF). However, pretreatment of these cells with SF had no effect on the number of IL-3Rs expressed at the cell surface nor their affinity for IL-3. Interestingly, although, SF did induce the rapid and transient serine- and threonine-specific phosphorylation of the beta IL-3 subunit of the IL-3R. This serine/threonine phosphorylation was also observed with the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate, and both the 12-O-tetradecanoylphorbol-13-acetate- and SF-induced phosphorylation of the IL-3R could be inhibited with the highly specific protein kinase C inhibitor, bisindolylmaleimide (Compound 3), suggesting that SF might be stimulating this phosphorylation via protein kinase C. This SF-induced phosphorylation also occurred within 10 min of incubation at 4 degrees C, indicating that this might be a relatively early event in the c-kit signaling pathway. Last, this SF-induced phosphorylation of the IL-3R occurred in the presence of the tyrosine kinase inhibitor, genistein, at levels which blocked the autophosphorylation of c-kit. This suggests that c-kit might be capable of mediating this cross-talk phenomenon in the absence of its endogenous tyrosine kinase activity. |
