PERK在胰腺酶噬发生中的作用及其信号通路机制研究

酶噬指胰腺腺泡细胞内酶原颗粒选择性自噬现象，具有降解异常激活的胰蛋白酶原作用，是一种新发现的胰腺内源性保护机制，首次于2011年在实验性急性胰腺炎模型中被发现，但其发生机制尚未阐明。近期我们采用Ca2+-ATP酶抑制剂诱导胰腺腺泡细胞产生内质网应激，发现可增强雨蛙素诱导的酶噬效应，并伴有内质网应激相关的蛋白激酶R样内质网激酶（PERK）表达上调，这提示内质网应激参与酶噬的调控，但是否通过PERK信号通路介导尚待进一步研究。本课题拟以雨蛙素诱导的小鼠和稳定表达GFP-LC3融合蛋白的胰腺AR42J细胞为研究对象，采用电镜、免疫荧光、RT-PCR、Western blot等方法和技术，通过siRNA进行PERK基因功能获得和缺失实验，探讨PERK在酶噬发生中的作用及其下游信号通路机制（elF2α-ATF4/CHOP和KEAP1-NRF2），旨在阐明酶噬的发生机制，并探索急性胰腺炎新的治疗靶点。

Zymophagy is defined as selective autophagy of zymogen granules in pancreatic acini, which degrades abnormally activated trypsinogen. Zymophagy is newly found endogenous protective mechanism in pancreas and was first reported by foreign researchers in 2011.Its mechanism is yet unclear now. Recently we adopted calcium ions-ATPase inhibitors,thapsigargin in pancreatic acini to induce endoplasmic reticulum stress and found the effects of zymophagy induced by bombsin had been enhanced with concurrent elevation of the expression of mRNA and protein of protein kinase R-like endoplasmic reticulum kinase(PERK). These findings suggest that endoplasmic reticulum stress has regulating effects on zymophagy，which needs further study wheather the regulating effects is mediated by PERK or not. Using models of mice and AR42J acinar cells treated by bombsin with the strategy of loss and gain of function by siRNA, this project is planned to explore the roles of PERK and its signal pathway(elF2α-ATF4/CHOP and KEAP1-NRF2) in mediating zymophagy. The aim of this project is to elucidate the mechanism of zymophagy, which will be helpful to find new therapeutic targets for acute pancreatitis.