Patrick Shiu

BIOGRAPHY

RESEARCH INTERESTS:
Research description
Our research interest is focused on gene regulation by post-transcription gene silencing system (PTGS). In the PTGS system, a transgenic aberrant RNA (aRNA) is converted into a double-stranded RNA (dsRNA) by the action of a RNA-directed RNA polymerase, and this dsRNA is cut into fragments of 21-23 nucleotides in length (small interfering or siRNA). These fragments act as guide RNAs for an ATP-dependent cleavage of homologous cytoplasmic mRNA. Recently, we have discovered a novel system of targeted gene silencing that operates after karyogamy, namely Meiotic Silencing by Unpaired DNA (MSUD). In the MSUD system, the diploid cell (zygote) scans the entire genome and compares the pairing of any DNA segment with its homolog during homologous pairing stage. DNA unpaired with a homologous sequence generates a sequence-specific signal. This signal destroys existing transcripts originating both from unpaired and paired DNA sequences homologous to it. MSUD requires the function of SAD-1, a RNA-directed RNA polymerase (RdRP). RdRP has been implicated in many PTGS systems, such as co-suppression in plants, RNA interference (RNAi) in animals and quelling in fungi.

EDUCATION:
PhD, 2000 University of British Columbia


HOME PAGE
http://www.biosci.missouri.edu/shiu/