2Molecular Medical Center for Cardiovascular Diseases, Fu Wai Cardiovascular Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, 100037 Beijing, China; fax: +86-10-6831-3012; E-mail: firstname.lastname@example.org; email@example.com
3Department of Pharmacology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 430030 Wuhan, China; E-mail: firstname.lastname@example.org
* To whom correspondence should be addressed.
Received April 2, 2007; Revision received June 4, 2007
In the present study, a yeast two-hybrid screening system was used to identify the interaction partners of cardiac troponin I-interacting kinase (TNNI3K) that might serve as regulators or targets, and thus in turn to gain some insights on the roles of TNNI3K. After screening the adult heart cDNA library with a bait construct encoding the ANK motif of TNNI3K, antioxidant protein 1 (AOP-1) was isolated. The interaction between TNNI3K and AOP-1 was confirmed by the in vitro binding assay and coexpression experiments in vivo. The colocalization of TNNI3K and AOP-1 was clarified by confocal immunofluorescence. Moreover, coexpression of AOP-1 inhibited TNNI3K kinase activity in the in vitro kinase assay.
KEY WORDS: AOP-1, protein kinase, protein-protein interaction, TNNI3K, yeast two-hybrid system