Our Science – Ziegelbauer Website

Joseph M Ziegelbauer, Ph.D.

HIV and AIDS Malignancy Branch Investigator Building 10, Room 6N110 NCI-Bethesda Bethesda, MD 20892 Phone:   301-594-6634 Fax:   Fax Number not listed E-Mail:   ziegelbauerjm@mail.nih.gov

Biography

Dr. Joseph Ziegelbauer received a B.S. from Cornell University with a major in biology and focus on biochemistry while working in the lab of Dr. John Lis. He then joined the laboratory of Dr. Robert Tjian for his graduate research where he received his Ph.D. from the University of California - Berkeley. Later, he began studying viral microRNAs in the laboratory of Dr. Don Ganem at the University of California - San Francisco. Dr. Ziegelbauer joined NCI in 2008. His primary focus is elucidating the functions of microRNAs expressed by Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8).

Research

Multiple groups recently discovered that KSHV, which is responsible for Kaposi's sarcoma, multicentric Castleman's disease and primary effusion lymphoma, expresses multiple microRNAs. Small non-coding RNAs called microRNAs have become newly appreciated molecules for gene regulation with each microRNA potentially targeting hundreds of target genes for repression. KSHV microRNAs are expressed during latency and represent an alternative method to alter host gene expression without generating viral proteins that could be detected by the host immune system. However, a current challenge is identifying the targets of microRNAs in order to determine the functions of microRNAs. To address this challenge, we developed a novel system to identify host targets of virally encoded microRNAs using a combination of gain and loss of microRNA function experiments, followed by expression profiling and sequence analysis. This dataset represents one of the largest microRNA target databases known since we have individually inhibited and expressed all seventeen viral microRNAs in multiple cell types. The first validated microRNA target from this approach was the human gene BCL2-Associated Transcription Factor 1 (BCLAF1). Note this target may have been missed using other common microRNA target prediction methods. Further studies revealed BCLAF1 may inhibit viral replication.

We are currently analyzing BCLAF1, other validated microRNA targets and potential targets identified by our screen. The goal is to validate additional host targets of viral microRNAs in order to better understand microRNA targeting, viral pathogenesis and to discover novel anti-viral and anti-tumor therapeutic targets.

This page was last updated on 12/8/2008.