Research


MicroRNA and Innate Immunity

Dr Kok, Kin Hang (郭健恒)

Research Assistant Professor, Department of Biochemistry

BSc (HKBU); MMedSc, PhD (HK)

Contact
Email: khkok@hku.hk
Tel: (852) 2819 9487; (852) 2819 2812 (Lab)
Office: L3-54, Laboratory Block, 21 Sassoon Road, Hong Kong

Research Description:

My research focuses on microRNA biogenesis and innate immunity in mammals. MicroRNAs have been extensively studied in the past few years for their roles in development, tumorigenicity, metastasis, and innate immunity. Precise temporal and spatial expression of microRNA expression is required for many biological processes. Abnormal microRNA expression may cause severe developmental defects and tumor formation. Dysregulation of microRNA biogenesis is one of the major causes of abnormal microRNA expression. One of my current projects is to characterize TRBP (a component of the RNA-Induced Silencing Complex, RISC) and its role in microRNA biogenesis and tumor formation. In addition, a new TRBP spliced variant has been identified and our data suggest that this TRBP isoform may negatively regulate microRNA biogenesis to exert an impact on tumorigenesis.

Publications, Achievements, and Grants:

Selected Publications:

  • Kok KH, Lui PY, Ng MH, Siu KL, Au WN, Jin DY. PACT functions as a cellular activator of RIG-I to facilitate innate antiviral response. Cell Host & Microbes. 2011 9:299-309.
  • Chan CP, Kok KH, Jin DY. CREB3 subfamily transcription factors are not created equal: Recent insights from global analyses and animal models. Cell & Bioscience. 2011 1:6.
  • Kok KH, Lei T, Jin DY. Identification and validation of the cellular targets of virus-encoded microRNAs. Methods Mol Biol. 2010 667:319-26.
  • Kok KH, Lei T, Jin DY. siRNA and shRNA screens advance key understanding of host factors required for HIV-1 replication. Retrovirology 2009 6(1):78.
  • Siu KL, Kok KH, Ng MH, Poon VK, Yuen KY, Zheng BJ, Jin DY. Severe Acute Respiratory Syndrome Coronavirus M Protein Inhibits Type I Interferon Production by Impeding the Formation of TRAF3-TANK-TBK1/IKKe Complex. J Biol Chem. 2009 284(24):16202-9.
  • Choy EY, Siu KL, Kok KH, Lung RW, Tsang CM, To KF, Kwong DL, Tsao SW, Jin DY. An Epstein-Barr virus-encoded microRNA targets PUMA to promote host cell survival. J Exp Med. 2008 205(11):2551-60.
  • Choy EY, Kok KH, Tsao SW, Jin DY. Utility of Epstein-Barr virus-encoded small RNA promoters for driving the expression of fusion transcripts harboring short hairpin RNAs. Gene Ther. 2008 15(3):191-202.
  • Kok KH, Ng MH, Ching YP, Jin DY. Human TRBP and PACT directly interact with each other and associate with dicer to facilitate the production of small interfering RNA. J Biol Chem. 2007 282(24):17649-57.
  • Kok KH, Jin DY. Influenza A virus NS1 protein does not suppress RNA interference in mammalian cells. J Gen Virol. 2006 87:2639-44.
  • Ng DC, Chan SF, Kok KH, Yam JW, Ching YP, Ng IO, Jin DY. Mitochondrial targeting of growth suppressor protein DLC2 through the START domain. FEBS Lett. 2006 580(1):191-8.
  • Kok KH, Jin DY. “RNAi in Xenopus Embryos” in Gene Silencing by RNA Interference: Technology and Application, edited by Muhammad Sohail. CRC Press. 2002
  • Zhou Y, Ching YP, Kok KH, Kung HF, Jin DY. Post-transcriptional suppression of gene expression in Xenopus embryos by small interfering RNA. Nucleic Acids Res. 2002 30(7):1664-9.
  • Wong CM, Chun AC, Kok KH, Zhou Y, Fung PC, Kung HF, Jeang KT, Jin DY. Characterization of human and mouse peroxiredoxin IV: evidence for inhibition by Prx-IV of epidermal growth factor- and p53-induced reactive oxygen species. Antioxid Redox Signal. 2000 2(3):507-18.
  • Lau GT, Wong OG, Chan PM, Kok KH, Wong RL, Chin KT, Lin MC, Kung HF, Chow KL. Embryonic XMab21l2 expression is required for gastrulation and subsequent neural development. Biochem Biophys Res Commun. 2001 280(5):1378-84.
  • Peng Y, Kok KH, Xu RH, Kwok KH, Tay D, Fung PC, Kung HF, Lin MC. Maternal cold inducible RNA binding protein is required for embryonic kidney formation in Xenopus laevis. FEBS Lett. 2000 482(1-2):37-43.
  • Zhou Y, Kok KH, Chun AC, Wong CM, Wu HW, Lin MC, Fung PC, Kung H, Jin DY. Mouse peroxiredoxin V is a thioredoxin peroxidase that inhibits p53-induced apoptosis. Biochem Biophys Res Commun. 2000 268(3):921-7.