Upregulation of actin-like gene expression in giant freshwater prawns Macrobrachium rosenbergii infected with Metschnikowia bicuspidata.
The giant freshwater prawn Macrobrachium rosenbergii is commercially cultured throughout the world including Taiwan. From 1992 to 1995, Taiwanese production decreased by approximately 50% due to disease. The yeast Metschnikowia bicuspidata is considered to be one of the major causes of white muscle disease, but the molecular mechanism of its pathogenesis is not known. Using RNA differential display (DD) with muscle and hepatopancreatic tissue, we identified a 324 nucleotide (nt) message specifically expressed by M. rosenbergii infected with M. bicuspidata but not in the controls. A ribonuclease protection assay (RPA) confirmed expression in both tissues. RPA data also revealed an additional 230 bp mRNA message that was not identified by DD. Using RNA ligase-mediated rapid amplification of 5' cDNA ends (5'-RACE), we successfully isolated a 1357 bp full-length gene (c57) that showed 92 and 87% sequence identity to the actin gene of the Kuruma shrimp Marsupenaeus japonicus (also called Penaeus japonicus) (GenBank accession number AB055975) and the beta-actin gene of the white shrimp Litopenaeus vannamei (also called Penaeus vannamei) (GenBank accession number AF300705), respectively. The deduced amino acid sequence of c57 showed 83 % sequence similarity to M. japonicus and L. vannamei actin proteins. Based on this high homology, we suggest that upregulation of actin expression in the muscle and hepatopancreas is part of the shrimp response to M. bicuspidata infection. Increased expression may be related to repair of tissues damaged by yeast infection.
Su
Hung-Yi
HY
Institute of Biotechnology, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan, ROC.
Wang
Pei-Chi
PC
Lien
Yi-Yang
YY
Tsai
Ming-An
MA
Liu
Shyh-Shyan
SS
Wu
Kun-Chan
KC
Hsieh
Cheng-Hung
CH
Chen
Shih-Chu
SC
D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D020869:Gene Expression Profiling; D043143:Hepatopancreas / Q000378:metabolism; D008969:Molecular Sequence Data; D009132:Muscles / Q000378:metabolism; D033541:Palaemonidae / Q000378:metabolism* / Q000382:microbiology*; D004718:Saccharomycetales; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D015854:Up-Regulation
D000199:Actins; D017931:DNA Primers