0000000000417431
AUTHOR
Marco Cattaruzza
Clusterin gene expression in apoptotic MDCK cells is dependent on the apoptosis-inducing stimulus
Abstract Clusterin (Apolipoprotein J, complement lysis inhibitor) is a widely expressed multifunctional glycoprotein. The expression of clusterin mRNA has been reported to be elevated in a broad spectrum of apoptotic or degenerative tissues. More recently, it was shown that within these tissues clusterin is expressed in the surviving rather than in the dying cells, and that clusterin gene expression is actually down-regulated in the apoptotic cells. We have studied the expression of the clusterin gene in apoptotic MDCK cells. Cell death was initiated by three different stimuli: application of the steroid hormone antagonist RU 486, activation of protein kinase C by the application of the pho…
Apoptotic Cell Debris and Phosphatidylserine-Containing Lipid Vesicles Induce Apolipoprotein J (Clusterin) Gene Expression in Vital Fibroblasts
The molecular events in cells undergoing programmed cell death (apoptosis) are well studied; however, the response of the surviving neighbor cells to local cell death is largely uncharacterized. Apolipoprotein J (clusterin) is an 80-kDa glycoprotein that has been implied in cytoprotection of the vital cells, presumably by assisting in the clearance of apoptotic vesicles and membrane remnants. Its mRNA is specifically up-regulated in the vital cells of apoptotic tissues. The molecular mechanisms, however, leading to this response are not known. We here show that exposure of vital fibroblasts to apoptotic vesicles, disrupted vital cells, and trypsin-treated membrane remnants induces apoJ mRNA…