Identification and functional study of a shrimp Relish homologue.
Rel/NF-kappaB transcription factors play central roles in induction and regulation of innate immune responses. Here we describe the identification and functional analysis of a Relish homologue, LvRelish and its shorter isoform sLvRelish, from the Pacific white shrimp, Litopenaeus vannamei. The LvRelish gene has 22 exons in approximately 15 kb genomic sequence. The full-length cDNA of LvRelish is 4071 bp with an open reading frame that encodes 1207 amino acids. LvRelish contains a conserved Rel homology domain (RHD), a nucleus localization signal, an IkappaB-like domain (six ankyrin repeats), and a death domain, suggesting that it belongs to the class I NF-kappaB. sLvRelish cDNA is 1051 bp encoding 317 amino acids. It shares the RHD region with LvRelish. RT-PCR analysis showed that LvRelish and sLvRelish mRNAs were expressed at different levels in tissues. Western blot analysis showed that recombinant intact LvRelish could be cleaved into two fragments in S2 cells, and immunofluorescence assay showed that the plasmid-expressed LvRelish protein was seen both in the cytoplasm and the nucleus. Electrophoretic mobility shift assay showed that recombinant RHD of LvRelish in S2 cells bound specifically with Drosophila melanogaster kappaB motifs in vitro. Both the LvRelish and its RHD domain transactivated the reporter gene controlled by the 5' flanking region of penaeidin 4, an antibacterial peptide of shrimp, suggesting that LvRelish can regulate the transcription of penaeidin 4 gene. Identification of LvRelish will help us better understand shrimp immunity and may help obtain more effective methods to prevent shrimp diseases.
Huang
Xian-De
XD
State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen (Zhong shan) University, 135 Xingang Road West, Guangzhou 510275, PR China.
Yin
Zhi-Xin
ZX
Liao
Ji-Xiang
JX
Wang
Pei-Hui
PH
Yang
Li-Shi
LS
Ai
Hua-Shui
HS
Gu
Zhi-Hua
ZH
Jia
Xiao-Ting
XT
Weng
Shao-Ping
SP
Yu
Xiao-Qiang
XQ
He
Jian-Guo
JG
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005786:Gene Expression Regulation; D023061:Gene Order; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000235:genetics* / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*
D014157:Transcription Factors