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GENOMICS
DNA Sequencing
Genotyping / GeneScan
Real-Time PCR
Oligo Synthesis
GeneChip Probe Array
Custom Spotted Array

PROTEOMICS
Protein Sequencing
Mass Spectrometry

BIOINFORMATICS
GCG / SeqWeb
Molecular Modeling
Internet Resources

My research interest is improving shrimp aquaculture production through molecular biology approach. The three main projects currently conducted in my laboratory are described below.

Molecular cloning and functional analysis of a cytoplasmic þ-actin promoter gene from the white shrimp, Penaeus vannamei ----- Infectious disease is one of the major problems in shrimp aquaculture. We apply modern recombinant DNA technology to produce disease-resistant strains of shrimp by genetic transformation. The most critical factor of developing a high efficient gene transformation system is the choice of a promoter which directs the expression of the foreign gene in the animal. Our focus is identifying a constitutional cytoplasmic, and also not developmentally regulated promoter from P. vannamei. The positive functional promoter sequences will be used to construct expression vectors for producing transgenic shrimp with desirable traits.

Molecular cloning and expression of growth regulatory neuropeptides of crustaceans ----- The main neuroendocrine axis of crustaceans is constituted by the medulla terminalis X-organ-sinus gland system in the eyestalk. A variety of hormonal peptides are synthesized in the X-organ and transported via axonic flow to the sinus gland and released into the hemolymph. The three peptides, crustacean hyperglycemic hormone (CHH), molt-inhibiting hormone (MIH), and vitellogenesis-inhibiting hormone (VIH), play an important role in many physiological responses including growth and reproduction. We are interested in studying the structure-function relationship as well as the identity, synthesis and processing of these neuropeptides. Our present work is to develop large-scale production of these recombinant hormones via a yeast protein expression system. The primary goal is to determine the biological activity of each neuropeptide and to examine the precise physiological roles of these hormones in the control of growth and maturation of the marine shrimp P. vannamei.

A molecular approach to improve shrimp production by sex-reversal technology (Collaboration with Dr. Spencer R. Malecha) ----- Marine shrimp aquaculture production could be improved by taking advantage of female-superior sexual dimorphism by producing all females from matings of normal female parents with females that have been sex-reversed to Amale@ implanted with the male sex-determining androgenic hormone (AH) from the androgenic gland (AG). This work involved in identifying the AH protein from the male shrimp. P. vannamei. The purified AH protein after confirming to be the active element for sex reversal process, will be subjected to amino acid sequence analysis and polyclonal antibody production. The full-length cDNA encoding the AH protein will be obtained by screening the AG-cDNA library constructed using the commercial available cDNA library synthesis kit. The long-range goal of this project is to obtain large quantity of the AH protein for use in producing all-female marine shrimp.

GREENWOOD MOLECULAR BIOLOGY FACILITY
Gilmore Hall 411  Open: 9 AM - 7 PM HST
Phone 1-808-956-6718 | Fax 1-808-956-9589 | E-mail biotech@hawaii.edu