Rabbit Anti-HSPA5 Polyclonal antibody

MiR-206 acts as a potential tumor suppressor during carcinogenesis and a regulatory factor in osteoblasts differentiation, but its modulatory mechanism remains unclear. In this study, we used a quantitative proteomics method, difference gel electrophoresis (DIGE), to profile the protein variation in A549 lung cancer cells with and without miR-206 transfection. We identified a total of 17 differently expressed proteins including 5 up-regulated and 12 down-regulated proteins affected by miR-206 in A549 cells. We further constructed a protein network linked 17 differently expressed proteins with 106 computationally predicted miR-206 targets, and identified 8 "hub" genes (CALR, CTSD, ENO1, HSPA5, CDC42, HSPD1, POLA1, and SMARCA4) within the network, which may represent important miR-206 functional gene targets. In conclusion, in this study, we identified several candidate functional target genes for miR-206, which is helpful to further explore its mechanisms during carcinogenesis and osteogenesis, and we also proposed a novel proteomic strategy to identify functionally important gene targets for microRNA.

Hepatic steatosis is the initial stage of nonalcoholic fatty liver disease (NAFLD) and may predispose to more severe hepatic disease, including hepatocellular carcinoma. Endoplasmic reticulum (ER) stress has been recently implicated as a novel mechanism that may lead to NAFLD, although the genetic factors invoking ER stress are largely unknown. During a screen for liver defects from a zebrafish insertional mutant library, we isolated the mutant cdipt(hi559Tg-/+) (hi559). CDIPT is known to play an indispensable role in phosphatidylinositol (PtdIns) synthesis. Here we show that cdipt is expressed in the developing liver, and its disruption in hi559 mutants abrogates de novo PtdIns synthesis, resulting in hepatomegaly at 5 days postfertilization. The hi559 hepatocytes display features of NAFLD, including macrovesicular steatosis, ballooning, and necroapoptosis. Gene set enrichment of microarray profiling revealed significant enrichment of endoplasmic reticulum stress response (ERSR) genes in hi559 mutants. ER stress markers, including atf6, hspa5, calr, and xbp1, are selectively up-regulated in the mutant liver. The hi559 expression profile showed significant overlap with that of mammalian hepatic ER stress and NAFLD. Ultrastructurally, the hi559 hepatocytes display marked disruption of ER architecture with hallmarks of chronic unresolved ER stress. Induction of ER stress by tunicamycin in wild-type larvae results in a fatty liver similar to hi559, suggesting that ER stress could be a fundamental mechanism contributing to hepatic steatosis. Conclusion: cdipt-deficient zebrafish exhibit hepatic ER stress and NAFLD pathologies, implicating a novel link between PtdIns, ER stress, and steatosis. The tractability of hi559 mutant provides a valuable tool to dissect ERSR components, their contribution to molecular pathogenesis, and evaluation of novel therapeutics of NAFLD. (HEPATOLOGY 2011; 54:452-462)