Department of Biological Sciences

PhD (Univ of British Col, Canada)

Research interests

Biology and biotechnology of antifreeze proteins; Marine biotechnology; Transgenic fish; Molecular endocrinology; Proteomics, structural biology; Cancer biology.

Background

(A) Functional genomics of shrimp white spot syndrome virus

Shrimp aquaculture, an important industry worldwide, has unfortunately been devastated by the spread of viral pathogens, notably the white spot syndrome virus (WSSV) during the last two decades. So far, there is no effective treatment method. WSSV genome contains a 305 KB double stranded circular DNA, which has the capacity to encode 181 open reading frames (ORFs) of 50 amino acids or more. However, in contrast with the best studied baculoviruses, only a few WSSV genes have been reported.

(B) Functional genomics of Singapore grouper iridovirus

Grouper iridoviruses also cause serious infection, mortality and economic loss for many farmed fishes in the Asian-Pacific region. Our previous studies on Singapore grouper iridovirus (SGIV) have revealed that 1) it is a double-stranded DNA virus that consisted of 140,131 nucleotide bp and 162 predicted ORFs; 2.) More that 50% of these ORFs encoded for novel proteins with unknown functions 3) the presence of 51 viral proteins by proteomics study; 4) transcriptional profiling of SGIV genes using DNA micro-array technology. We are currently extending our research to virus protein structure and function.

(C) Human cancer biology

Colorectal cancer (CRC) is the second leading killer cancer worldwide. CRC formation is a multi-step process involving numerous gene mutations which results in the loss of function of tumor suppressor genes as well as the activation of oncogenes. Yet, the precise mechanism by which tumor develops remains elusive.

Objectives

(A) Functional and structural genomics of shrimp white spot syndrome virus

To fully understand the biology of WSSV, host interaction and pathogenesis.
To devise specific and effective treatment protocol for the disease outbreak.

(B) Functional and structural genomics of SGIV

To identify and characterize putative SGIV proteins involved in transcriptional regulation and cell cycle control to bridge the gap between gene products and function.
To establish a platform for functional genomics of large dsDNA viral pathogens using SGIV as a prototype.
To create new knowledge for design of small molecular inhibitors to control the viral disease. The structural-based design of small molecule inhibitors will represent a new and promising approach to block viral infection.

(C) Human cancer biology

To understand the biology, tumorigenesis of CRC.
To identify biomarkers for CRC and drug candidates for treatment.

Current Main Projects:

(A) Functional and structural genomics of shrimp white spot syndrome virus

Proteomic analysis of the WSSV viral proteins. We have successfully identified numerous viral proteins using 2D gel electrophoresis and mass spectrometry. Many of these are envelope proteins and their presence and localization confirmed by protein expression and microscopy.
Global expression of all ORFs for protein micro-arrays. Protein array is an emerging technology that allows high-throughput screening of protein functions, protein-protein interaction and drugs discovery. Using the Gateway cloning technology, we are now expressing the ORFs in both prokaryotic and eukaryotic expression systems.
Structural genomics of WSSV. This program includes the elucidation of the overall viral structure and symmetry of the virions and the nuclocapsids by cryoelectron microscopy and 3D reconstruction, elucidation of small molecular weight protein by protein NMR and elucidation of large and membrane proteins by X ray crystallography. The structural elucidation of WSSV proteins will provide important information on the design of specific inhibitors and peptide mimetics.

(B) Functional and structural genomics of Singapore grouper iridovirus

To determine 3D structures of representative and novel SGIV proteins by NMR and X-ray crystallography.
To understand how the virus is able to recruit certain cellular metabolic pathways for its replication.
To elucidate SGIV viral DNA packaging, release and virus assembly mechanisms.

(C) Human cancer biology

Proteomic investigations of CRC. CRC and the adjacent normal mucosa tissues have been collected after surgical resection from over 35 patients with full record of personal and pathological information. We have used 2D gel electrophoresis and Isotope-coded Affinity Tags (ICATs) to compare the normal versus cancer samples. Several candidates have been identified. Present experiments focus on improving sensitivity of protein identification, and validation of potential biomarkers or drug targets.
Signaling mechanisms. The role of TGF-B, SMAD proteins and other oncogenes in tumorgenesis is now being investigated.

Current grant support

Structural Genomics of Shrimp White Spot Syndrome Virus (2004-2007)
Analysis of protein-protein interactions between white spot syndrome virus and its host protein microarray (2005-2007)
Oncoproteomics in Biomarker and Drug Discovery (2005-2008)
Gastric Cancer Biomarker Discovery (2005-2008)
Proteomic Investigation of Colorectal Cancer (2003-2006)

Selected Publications:

Liu Y, Li Z, Lin Q, Kosinski J, Seetharaman J, Bujnicki JM, Sivaraman J, Hew CL. (2007) Structure and Evolutionary Origin of Ca-Dependent Herring Type II Antifreeze Protein. PLoS ONE. 20;2:e548.
Tang X, Hew CL (2007) Expression, purification and crystallization of two major envelope proteins from white spot syndrome virus. Acta Crystallograph Sect F Struct Biol Cryst Commun. 63:624-6.
Chen Y, Low TY, Choong LY, Ray RS, Tan YL, Toy W, Lin Q, Ang BK, Wong CH, Lim S, Li B, Hew CL, Sze NS, Druker BJ, Lim YP. (2007) Phosphoproteomics identified Endofin, DCBLD2, and KIAA0582 as novel tyrosine phosphorylation targets of EGF signaling and Iressa in human cancer cells. Proteomics. 7:2384-97
Li Z, Lin Q, Chen J, Wu JL, Lim TK, Loh SS, Tang X, Hew CL. (2007) Shotgun identification of structural proteome of shrimp white spot syndrome virus and iTRAQ differentiation of envelope and nucleocapsid subproteomes. Mol Cell Proteomics. (in press)
Zhang H, Lin Q, Ponnusamy S, Kothandaraman N, Lim TK, Zhao C, Kit HS, Arijit B, Rauff M, Hew CL, Chung MC, Joshi SB, Choolani M. (2007) Differential recovery of membrane proteins after extraction by aqueous methanol and trifluoroethanol. Proteomics. 7:1654-63.
Tang X, Wu J J.Sivaraman* and Hew CL* (2007) Crystal Structure of Two Major Envelope Proteins VP26 and VP28 from White Spot Syndrome Virus (WSSV) Shed Light on their Evolutionary Relationship. J Virol. 81:6709-17.
Chen J, Li Z and Hew CL. (2007) Characterization of a novel envelope protein WSV010 of shrimp white spot syndrome virus and its interaction with a major viral structural protein VP24. Virology 364: 208-13.
Liu Y, Wu J, Song J, Sivaraman J, Hew CL (2006) Identification of a novel nonstructural protein, VP9, from white spot syndrome virus: its structure reveals a ferredoxin fold with specific metal binding sites. J Virol. 80:10419-27.

Chen LM, Wang F, Song W, Hew CL (2006) Temporal and differential gene expression of Singapore grouper iridovirus. J Gen Virol. 87:2907-15.

Liu Y, Sivaraman J, Hew CL (2006) Expression, purification and crystallization of a novel nonstructural protein VP9 from white spot syndrome virus. Acta Crystallograph Sect F Struct Biol Cryst Commun. 62:802-4.

Tay TL, Lin Q, Seow TK, Tan KH, Hew CL, Gong Z. (2006) Proteomic analysis of protein profiles during early development of the zebrafish, Danio rerio. Proteomics. 6:3176-88.

Li M, Rosenshine I, Yu HB, Nadler C, Mills E, Hew CL, Leung KY (2006) Identification and characterization of NleI, a new non-LEE-encoded effector of enteropathogenic Escherichia coli (EPEC). Microbes Infect. 8:2890-8.

Du N, Liu XY, Hew CL (2006) Aggregation of antifreeze protein and impact on antifreeze activity. J Phys Chem B Condens Matter Mater Surf Interfaces Biophys. 110:20562-7.

Bi X, Lin Q, Foo TW, Joshi S, You T, Shen HM, Ong CN, Cheah PY, Eu KW, Hew CL (2006) Proteomic analysis of colorectal cancer reveals alterations in metabolic pathways: mechanism of tumorigenesis. Mol Cell Proteomics. 5:1119-30.

Lo SL, You T, Lin Q, Joshi SB, Chung MC, Hew CL (2006) SPLASH: systematic proteomics laboratory analysis and storage hub. Proteomics. 6:1758-69.

Song W, Lin Q, Joshi SB, Lim TK, Hew CL (2006) Proteomic studies of the Singapore grouper iridovirus. Mol Cell Proteomics. 5:256-64.

Li Z, Lin Q, Yang DS, Ewart KV, Hew CL (2004) The role of Ca 2+-coordinating residues of herring antifreeze protein in antifreeze activity. Biochemistry. 43:14547-54.

Song WJ, Qin QW, Qiu J, Huang CH, Wang F, Hew CL (2004) Functional genomics analysis of Singapore grouper iridovirus: complete sequence determination and proteomic analysis. J Virol. 78:12576-90.

Li M, Rosenshine I, Tung SL, Wang XH, Friedberg D, Hew CL, Leung KY (2004) Comparative proteomic analysis of extracellular proteins of enterohemorrhagic and enteropathogenic Escherichia coli strains and their ihf and ler mutants. Appl Environ Microbiol. 70:5274-82.

Zhang X, Huang C, Tang X, Zhuang Y, Hew CL (2004) Identification of structural proteins from shrimp white spot syndrome virus (WSSV) by 2DE-MS. Proteins. 55:229-35.

Du N, Liu XY, Hew CL (2003) Ice nucleation inhibition: mechanism of antifreeze by antifreeze protein. J Biol Chem. 278:36000-4.

Chew FT, Ong SY, Hew CL (2003) Severe acute respiratory syndrome coronavirus and viral mimicry. Lancet. 361:2081.

Murray HM, Hew CL, Fletcher GL. (2003) Spatial expression patterns of skin-type antifreeze protein in winter flounder (Pseudopleuronectes americanus) epidermis following metamorphosis. J Morphol. 257:78-86.

Uzbekova S, Amoros C, Cauty C, Mambrini M, Perrot E, Hew CL, Chourrout D, Prunet P. (2003) Analysis of cell-specificity and variegation of transgene expression driven by salmon prolactin promoter in stable lines of transgenic rainbow trout. Transgenic Res. 12:213-27.

Low WK, Lin Q, Hew CL (2003) The role of N and C termini in the antifreeze activity of winter flounder (Pleuronectes americanus) antifreeze proteins. J Biol Chem. 278:10334-43.

Tan YP, Lin Q, Wang XH, Joshi S, Hew CL, Leung KY (2002) Comparative proteomic analysis of extracellular proteins of Edwardsiella tarda. Infect Immun. 70:6475-80.

Huang C, Zhang X, Lin Q, Xu X, Hew CL (2002) Characterization of a novel envelope protein (VP281) of shrimp white spot syndrome virus by mass spectrometry. J Gen Virol. 83:2385-92.

Huang C, Zhang X, Lin Q, Xu X, Hu Z, Hew CL (2002) Proteomic analysis of shrimp white spot syndrome viral proteins and characterization of a novel envelope protein VP466. Mol Cell Proteomics. 1:223-31.

Zhang X, Huang C, Xu X, Hew CL (2002) Identification and localization of a prawn white spot syndrome virus gene that encodes an envelope protein. J Gen Virol. 83:1069-74.

Zhang X, Huang C, Xu X, Hew CL (2002) Transcription and identification of an envelope protein gene (p22) from shrimp white spot syndrome virus. J Gen Virol. 83:471-7.

Islam NM, Hew CL, Kaczur V, Farid NR. (2001) Cleavage of the thyrotropin receptor. J Endocrinol Invest. 24:833-5.
Zhang X, Xu X, Hew CL (2001) The structure and function of a gene encoding a basic peptide from prawn white spot syndrome virus. Virus Res. 79:137-44.

Ando H, Hew CL, Urano A. (2001) Signal transduction pathways and transcription factors involved in the gonadotropin-releasing hormone-stimulated gonadotropin subunit gene expression. Comp Biochem Physiol B Biochem Mol Biol. 129:525-32. Review.

Li Z, Xiong F, Lin Q, d'Anjou M, Daugulis AJ, Yang DS, Hew CL (2001) Low-temperature increases the yield of biologically active herring antifreeze protein in Pichia pastoris. Protein Expr Purif. 21:438-45.

Fletcher GL, Hew CL, Davies PL. (2001) Antifreeze proteins of teleost fishes. Annu Rev Physiol. 63:359-90. Review.

Low WK, Lin Q, Stathakis C, Miao M, Fletcher GL, Hew CL (2001) Isolation and characterization of skin-type, type I antifreeze polypeptides from the longhorn sculpin, Myoxocephalus octodecemspinosus. J Biol Chem. 276:11582-9.

Miao M, Chan SL, Fletcher GL, Hew CL (2000) The rat ortholog of the presumptive flounder antifreeze enhancer-binding protein is a helicase domain-containing protein. Eur J Biochem. 267:7237-46.

Yeh S, Moffatt BA, Griffith M, Xiong F, Yang DS, Wiseman SB, Sarhan F, Danyluk J, Xue YQ, Hew CL, Doherty-Kirby A, Lajoie G. (2000) Chitinase genes responsive to cold encode antifreeze proteins in winter cereals. Plant Physiol. 124:1251-64.

Lin W, Wang HW, Sum C, Liu D, Hew CL, Chung B. (2000) Zebrafish ftz-f1 gene has two promoters, is alternatively spliced, and is expressed in digestive organs. Biochem J. 348:439-46.

Liu D, Chandy M, Lee SK, Le Drean Y, Ando H, Xiong F, Woon Lee J, Hew CL (2000) A zebrafish ftz-F1 (Fushi tarazu factor 1) homologue requires multiple subdomains in the D and E regions for its transcriptional activity. J Biol Chem. 275:16758-66.

Tong L, Lin Q, Wong WK, Ali A, Lim D, Sung WL, Hew CL, Yang DS. (2000) Extracellular expression, purification, and characterization of a winter flounder antifreeze polypeptide from Escherichia coli. Protein Expr Purif. 18:175-81.

Ando H, Ando J, Le Drean Y, Liu D, Xiong F, Hew CL (1999) Salmon gonadotropin IIbeta subunit promoter contains multiple DNA elements responsible for stimulation by gonadotropin-releasing hormone through protein kinase C-dependent and -independent pathways. Mol Cell Endocrinol. 157:143-52.

Garg RR, Bally-Cuif L, Lee SE, Gong Z, Ni X, Hew CL, Peng C. (1999) Cloning of zebrafish activin type IIB receptor (ActRIIB) cDNA and mRNA expression of ActRIIB in embryos and adult tissues. Mol Cell Endocrinol. 153:169-81.

Lin Q, Ewart KV, Yan Q, Wong WK, Yang DS, Hew CL (1999) Secretory expression and site-directed mutagenesis studies of the winter flounder skin-type antifreeze polypeptides. Eur J Biochem. 264:49-54.

Ju B, Xu Y, He J, Liao J, Yan T, Hew CL, Lam TJ, Gong Z. (1999) Faithful expression of green fluorescent protein (GFP) in transgenic zebrafish embryos under control of zebrafish gene promoters. Dev Genet. 25:158-67.

Lin Q, Ewart KV, Yang DS, Hew CL (1999) Studies of a putative ice-binding motif in winter flounder skin-type anti-freeze polypeptide. FEBS Lett. 453:331-4.

Ewart KV, Lin Q, Hew CL (1999) Structure, function and evolution of antifreeze proteins. Cell Mol Life Sci. 55:271-83. Review.