tailieunhanh - Báo cáo y học: "PLCb1-SHP-2 complex, PLCb1 tyrosine dephosphorylation and SHP-2 phosphatase activity: a new part of Angiotensin II signaling?"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: PLCb1-SHP-2 complex, PLCb1 tyrosine dephosphorylation and SHP-2 phosphatase activity: a new part of Angiotensin II signaling? | Calò et al. Journal of Biomedical Science 2011 18 38 http content 18 1 38 tì NSC The cost of publication in Journal of Biomedical Science Is borne by the National Science Council Taiwan JOURNAL OF BIOMEDICAL SCIENCE RESEARCH Open Access PLCP1-SHP-2 complex PLCP1 tyrosine dephosphorylation and SHP-2 phosphatase activity a new part of Angiotensin II signaling 1 t 2t 31 1 1 Lorenzo A Calò Luciana Bordin Paul A Davis Elisa Pagnin Lucia Dal Maso Gian Paolo Rossi Achille C Pessina1 and Giulio Clari2 Abstract Background Angiotensin II Ang II signaling occurs via two major receptors which activate non-receptor tyrosin kinases that then interact with protein tyrosin-phosphatases PTPs to regulate cell function. SHP-2 is one such important PTP that also functions as an adaptor to promote downstream signaling pathway. Its role in Ang II signaling remains to be clarified. Results Using cultured normal human fibroblasts immunoprecipitation and western blots we show for the first time that SHP-2 and PLCp 1 are present as a preformed complex. Complex PLCp 1 is tyr-phosphorylated basally and Ang II increased SHP-2-PLCP1 complexes and caused complex associated PLCp 1 tyr-phosphorylation to decline while complex associated SHP-2 s tyr-phosphorylation increased and did so via the Ang II type 1 receptors as shown by Ang II type 1 receptor blocker losartan s effects. Moreover Ang II induced both increased complex phosphatase activity and decreased complex associated PLCp 1 tyr-phosphorylation the latter response required regulator of G protein signaling RGS -2. Conclusions Ang II signals are shown for the first time to involve a preformed SHP-2-PLCP1 complex. Changes in the complex s PLCp 1 tyr-phosphorylation and SHP-2 s tyr-phosphorylation as well as SHP-2-PLCP1 complex formation are the result of Ang II type 1 receptor activation with changes in complex associated PLCb1 tyr-phosphorylation requiring RGS-2. These findings might significantly expand the number and .