An immune deficiency homolog from the white shrimp, Litopenaeus vannamei, activates antimicrobial peptide genes.
Invertebrates rely on innate immunity as the first line defense against microbes. In Drosophila, the inducible antimicrobial peptides (AMPs) regulated by the Toll and immune deficiency (Imd) pathways are important effectors in innate immunity. Here we report an immune deficiency homolog (LvIMD) from the white shrimp, Litopenaeus vannamei. The full-length cDNA of LvIMD is 758 bp with an open reading frame of 483 bp that encodes a putative protein of 160 amino acids including a death domain at the C-terminus. LvIMD death domain shows similarity to that of Drosophila IMD and human receptor interacting protein 1 (RIP1) of the tumor necrosis factor receptor (TNFR) pathway, with 27.9% and 26.4% identity, respectively. Phylogenetic analysis shows that LvIMD clusters with a predicted protein from the starlet sea anemone (Nematostella vectensis) independent to insect IMDs and vertebrates RIP1s. LvIMD mRNA is expressed in most tissues and is induced in hepatopancreas and hemocytes after immune challenge. Luciferase reporter assays confirm that LvIMD is able to induce the expression of AMP genes, including Drosophila Attacin A and shrimp Penaeidin 4 in S2 cells. To our knowledge, this is the first report that LvIMD participates in innate signaling to activate the expression of AMP genes in shrimp.
Wang
Pei-Hui
PH
State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen (Zhongshan) University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China.
Gu
Zhi-Hua
ZH
Huang
Xian-De
XD
Liu
Bo-Du
BD
Deng
Xie-xiong
XX
Ai
Hua-Shui
HS
Wang
Jing
J
Yin
Zhi-Xin
ZX
Weng
Shao-Ping
SP
Yu
Xiao-Qiang
XQ
He
Jian-Guo
JG
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D043143:Hepatopancreas / Q000276:immunology / Q000378:metabolism; D007113:Immunity, Innate / Q000235:genetics; D008954:Models, Biological; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D010802:Phylogeny; D017385:Sequence Homology; D015854:Up-Regulation
D023181:Antimicrobial Cationic Peptides; D029721:Drosophila Proteins; C439909:imd protein, Drosophila