Fyn kinase-dependent cellular events were related with skeletal muscle denervation. In the present study, we used a combination of techniques to measure ER stability and the related Gβ1γ2 trafficking following muscl...Fyn kinase-dependent cellular events were related with skeletal muscle denervation. In the present study, we used a combination of techniques to measure ER stability and the related Gβ1γ2 trafficking following muscle mobilization, and demonstrated a temporally and Fyn-dependent up-regulation of Ca2+ level in the mobilized muscle. In parallel, Fyn activity in ER was gradually decreased, which was accompanied by enhanced PTP1B activity and expressions of ER proteins (calnexin, Grp94, cyclophilin, and Hsp70). Moreover, during muscle mobilization, there was more membrane protein breakdown than protein synthesis, which probably featured robust Gβ1γ2 internalization, and Rab1-dependent transport into ER compartment;the signaling was related to disruption of PI3K-Akt signaling and decrement of muscular functions. Then, Gβ1γ2 trafficking is a key component necessary for the early recovery processes regarding muscle atrophy, which would be the therapeutic consideration for muscle repair and regeneration.展开更多
A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (S...A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.展开更多
文摘Fyn kinase-dependent cellular events were related with skeletal muscle denervation. In the present study, we used a combination of techniques to measure ER stability and the related Gβ1γ2 trafficking following muscle mobilization, and demonstrated a temporally and Fyn-dependent up-regulation of Ca2+ level in the mobilized muscle. In parallel, Fyn activity in ER was gradually decreased, which was accompanied by enhanced PTP1B activity and expressions of ER proteins (calnexin, Grp94, cyclophilin, and Hsp70). Moreover, during muscle mobilization, there was more membrane protein breakdown than protein synthesis, which probably featured robust Gβ1γ2 internalization, and Rab1-dependent transport into ER compartment;the signaling was related to disruption of PI3K-Akt signaling and decrement of muscular functions. Then, Gβ1γ2 trafficking is a key component necessary for the early recovery processes regarding muscle atrophy, which would be the therapeutic consideration for muscle repair and regeneration.
基金This work was sup-ported by the National Natural Science Foundation of China (Grant No. 30170615) and National Major Basis Study Develop-mental Plan 973 Project (TG2000016208).
文摘A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.
