title: Polymorphisms of anti-lipopolysaccharide factors in the swimming crab Portunus trituberculatus and their association with resistance/susceptibility to Vibrio alginolyticus.
abstract: Anti-lipopolysaccharide factor (ALF) is an important antimicrobial peptide (AMP) that can bind and neutralize major component of Gram-negative bacteria cell wall, lipopolysaccharide (LPS). Seven isoforms of anti-lipopolysaccharide factors (PtALF1-7) were previously identified from the swimming crab Portunus trituberculatus in our laboratory. Here, polymorphisms of PtALF1-7 were detected and their association with resistance/susceptibility to Vibrio alginolyticus (a main Gram-negative bacteria causing high mortality in P. trituberculatus) were investigated. We identified 127, 96, 103, 53 and 158 single nucleotide polymorphisms (SNPs) in genomic fragments of PtALF1-3, PtALF4, PtALF5, PtALF6 and PtALF7, respectively. Among them, totally sixteen SNPs were significantly associated with resistance/susceptibility to V. alginolyticus (P < 0.05). Of these sixteen SNPs, most were located in introns and noncoding exons, while two synonymous SNPs and one nonsynonymous SNP were in coding exons. Additionally, simple sequence repeats (SSRs) were only identified in introns and noncoding exons of PtALF4, PtALF5 and PtALF7. Although no significant difference of allele frequencies was found, these SSRs had different polymorphic alleles according to the repeat number between susceptible and resistant stocks. After further confirmation, polymorphisms investigated here might be applied as potential molecular markers for future selection of resistant strains to diseases caused by Gram-negative bacteria.
authors.affiliation: EMBL, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
authors.forename: Xihong
authors.initials: X
authors.lastname: Li
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Cui
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Chengwen
authors.initials: C
authors.lastname: Song
authors.forename: Guohui
authors.initials: G
authors.lastname: Shi
authors.forename: Chunlin
authors.initials: C
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics* / Q000276:immunology*; D007113:Immunity, Innate; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D044149:Vibrio alginolyticus / Q000502:physiology*
chemical_list: D023181:Antimicrobial Cationic Peptides; D060829:Arthropod Proteins; D020033:Protein Isoforms