Functional Characterization of Salt-Inducible Kinases in Secretory Glands

• Main Authors: Wei-Yao Chen, 陳煒堯
• Other Authors: Han-Yi E. Chou
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/96235418621824823822

碩士 === 國立臺灣大學 === 口腔生物科學研究所 === 101 === AMPK is involved in the maintenance of energy balance in human body. Salt-inducible kinases (SIK1/2/3 isoforms) belong to the AMP-activated protein kinase (AMPK) family, and were first cloned from the adrenal glands of rats fed with high salt diet. Through phosphorylation and subsequent cytoplasmic sequestration of the coactivator TORC2, SIKs can down-regulate transcriptional activation of the cAMP-response element-binding protein CREB. This SIK-dependent transcriptional regulation has been shown to be an important determinant for survival and protein, lipid and carbohydrate produce. SIKs also control iron homeostasis via regulate intracellular iron balance. in Aguilera’s lab, the paper published in 2012 showed that there is cooperation and sequential induction of SIK1 and SIK2 in neuron. Under stimulated, SIK1 and SIK2 will be induced in different time at the same organ. Base on the reference, was SIK2 also induced from the adrenal glands of rats fed with high salt diet? Immunohistochemistry approaches were used to determine the protein expression profile of all three SIK isoforms. In additional, SIK2 kinase activity is involved in its DCV function. Next, the western blotting and Quantitative PCR in Y1 mouse adrenocortical zona fasciculata tumor cell demonstrated that Y1 cell is a suitable cell line model for studying SIK2 function. Then, the Immunofluorescence staining showed that punctate distribution of SIK2 in cytoplasm resembling vesicles and SIK2 colocalization with DCV marker Rab27A.Thus, we suggest that SIK2 might play a dominant role in DCV secretion of adrenal cortex zone fasciculata. ACTH treatment induced SIKs express level and kinase activity changed. Further studies on the vesicle contain is the next step in our lab research.