Location & General Inquiries
10833 Le Conte Ave., 13-145 CHS
Los Angeles, CA 90095
Phone: (310) 825-6470 | Email
Fax: (310) 794-4161
Pathology Requests & Reports
(310) 825-8947 (UCLA)
(310) 267-2680 (outside UCLA)
Tissue Procurement and Banking Services (TPCL)
Phone: (310) 825-1717
Cardiac arrhythmias remain a major health problem, causing at least 250,000 deaths annually in the United States. Dr. Xu's long-term goal is to elucidate molecular signaling pathways involving the development of cardiac arrhythmias so that therapeutic targets for treatment and/or prevention can be identified.
p90 ribosomal S6 kinase (p90RSK) activity is significantly increased, and both FoxO1 and b-catenin are accumulated in the nuclei of cardiomyocytes in ischemic heart diseases, in which cardiac arrhythmias such as ventricular tachycardia and ventricular fibrillation frequently occur. In his lab, a sophisticated combination of biochemical, electrophysiological and molecular techniques has been exploited to define the roles of this kinase, transcription factor and co-transcription factor in the modulation of cardiac ion channels. The findings indicate that activation of p90RSK prolongs cardiac repolarization through phosphorylating voltage-gated outward K+ channels, and both FoxO1 and b-catenin attenuate the cardiac depolarization by suppressing NaV1.5 expression through inhibiting SCN5a promoter activity.