期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1993
卷号：90
期号：4
页码：1440-1444
DOI：10.1073/pnas.90.4.1440
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The rat peroxisome-proliferator-activated receptor (PPAR) was expressed in insect cells and was shown to bind to a cognate PPAR response element (PPRE) from the acyl-CoA oxidase gene. Upon purification, PPAR was no longer able to bind DNA, although binding could be restored by addition of insect cell extracts. We investigated whether the retinoid X receptor (RXR) could supplement for this accessory activity. The rat RXR alpha cDNA was cloned and it was found that addition of in vitro-translated RXR alpha to purified PPAR facilitated binding of PPAR to a PPRE. Furthermore, an additional activity, which appeared to be distinct from rRXR alpha, was found in COS cell nuclear extracts that enabled binding of PPAR to a PPRE. Transient expression of RXR alpha in CHO cells was found to be essential for the response of a chloramphenicol acetyltransferase reporter construct containing PPREs to activators of PPAR. These results raise the possibility of convergence of the PPAR and retinoid-dependent signaling pathways on promoters containing PPRE-like responsive elements.
