Investigating GLUT4 Trafficking in Muscle

摘要: GLUT4 trafficking in muscle cells has been studied to determine how distinct signalling pathways induce translocation. Two different cell models were adopted for these investigations; cardiomyocytes isolated from a transgenic mouse line expressing HA-GLUT4-GFP and L6 myotubes retrovirally HA-GLUT4. The constructs largely excluded the external membrane under basal conditions both models. was trafficked response all stimuli (insulin, contraction hypoxia) AICAR A-769662). By comparing anti-HA GFP signals at sarcolemma transverse tubules cardiomyocytes, it also be possible observe an enhancement of GSV fusion with following stimulation insulin contraction. This effect specific sarcolemma. Insulin-stimulation exocytosis not detected steady-state myotubes. Here, major insulin-stimulation AMPK-activation on internalisation. rate constant internalisation very rapid decreased during responses AMPK-activators A-769662. In internalising colocalised clathrin puncta indicates that is internalised via clathrin-mediated route. Investigations into amount recycling revealed large proportion cellular recycles surface conditions. additively mobilised cells. implies non-convergent mobilisation activation PKB/Akt AMPK pathways. Data obtained vitro kinase assay confirmed serine 237 TBC1D1 bone fide phosphorylation site. Furthermore, this site incubated activators using novel antibody phosphorylated 237. thesis discusses consequences importance multiple controls impinging traffic highlights advantages limitations kinetic studies processes.