title: An immune deficiency homolog from the white shrimp, Litopenaeus vannamei, activates antimicrobial peptide genes.
abstract: 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.
authors.affiliation: 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.
authors.forename: Pei-Hui
authors.initials: PH
authors.lastname: Wang
authors.forename: Zhi-Hua
authors.initials: ZH
authors.lastname: Gu
authors.forename: Xian-De
authors.initials: XD
authors.lastname: Huang
authors.forename: Bo-Du
authors.initials: BD
authors.lastname: Liu
authors.forename: Xie-xiong
authors.initials: XX
authors.lastname: Deng
authors.forename: Hua-Shui
authors.initials: HS
authors.lastname: Ai
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Zhi-Xin
authors.initials: ZX
authors.lastname: Yin
authors.forename: Shao-Ping
authors.initials: SP
authors.lastname: Weng
authors.forename: Xiao-Qiang
authors.initials: XQ
authors.lastname: Yu
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: He
mesh_terms: 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
chemical_list: D023181:Antimicrobial Cationic Peptides; D029721:Drosophila Proteins; C439909:imd protein, Drosophila