Melanin concentrating hormone (MCH) receptors are G protein-coupled receptors which control appetite and energy expenditure in mammals. Periplakin is an actin- and intermediate filament-binding protein that contributes to this receptorís desensitization. I asked whether MCH receptors mediate actin cytoskeletal rearrangements in response to hormone binding by investigating the effect of MCH on 3T3-L1 pre-adipocyte actin morphology as well as a downstream effecter of Gq, phospholipase C. 3T3-L1 pre-adipocytes were treated with MCH for varying times, fixed, and actin fibers were stained. Using fluorescence microscopy, cell morphology was categorized. A small, statistically significant change in actin morphology was observed with 2 minutes MCH. Phospholipase C activators and inhibitors mimic and disrupt morphology changes suggesting it participates in this pathway. Pharmacological disruption of actin filaments resulted in elevated MAPK activation and suggests actin may play a significant role in dampening receptor signaling.
|Presenter:||Scott Portwood (Graduate Student)|
|Time:||9:55 am (Session I)|