title: Three members in JAK/STAT signal pathway from the sea cucumber Apostichopus japonicus: Molecular cloning, characterization and function analysis.
abstract: The JAK/STAT signal transduction pathway plays a critical role in host defense against bacterial infections. In the present study, we firstly cloned the full-length cDNAs of three molecules in JAK/STAT cascade, STAT5, FOXP and SOCS2, from sea cucumber Apostichopus japonicus (denoted as AjSTAT5, AjFOXP, AjSOCS2, respectively) and investigated their immune functions towards Vibrio splendidus infection and LPS exposure. The AjSTAT5 cDNA was composed of 2643 bp consisting of 787 amino acid residues which included protein interaction domain, STAT-α domain, DNA binding domain and SH2 domain. The putative AjFOXP contained a ZnF_C2H2 domain, the leucine zipper-like domain and FH domain, all of which were thought to be the representative characteristics of FOXP subfamily. The deduced amino acids sequence of AjSOCS2 included an SH2 domain and SOCS box domain similar to vertebrate SOCS counterparts. Phylogenetic trees further supported that all these three identified proteins belonged to novel members of JAK/STAT signal pathway in sea cucumber. Tissue specific expression analysis showed that three genes were ubiquitously expressed in all examined tissues. AjSTAT5 and AjFOXP were both dominantly expressed in intestine, tentacle and respiratory tree, and weak in muscle. In contrary, the peak expression of AjSOCS2 was observed in muscle and lowest in respiratory tree. The V. splendidus challenge and LPS exposure could both significantly up-regulate the mRNA expression of three genes, in which AjSOCS2 showed opposite expression trends to those of AjSTAT5 and AjFOXP. Silencing the AjSTAT5 by siRNA depressed the AjFOXP expression, but induced the expression level of AjSOCS2, revealing that AjSTAT5 might directly modulate AjFOXP, and AjSOCS2 function primarily by acting as a potent inhibitor involve in JAK/STAT pathway. The present study would expand our understanding on JAK/STAT signaling transduction pathway in modulating the innate immune responses of sea cucumber.
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Yina
authors.initials: Y
authors.lastname: Shao
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China. Electronic address: lichenghua@nbu.edu.cn.
authors.forename: Chenghua
authors.initials: C
authors.lastname: Li
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Duan
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Qingxi
authors.initials: Q
authors.lastname: Han
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D051858:Forkhead Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D020868:Gene Silencing; D007113:Immunity, Innate / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology / Q000502:physiology; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010802:Phylogeny; D050799:STAT5 Transcription Factor / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D047528:Stichopus / Q000235:genetics* / Q000276:immunology*; D050826:Suppressor of Cytokine Signaling Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014733:Vibrio / Q000502:physiology
chemical_list: D051858:Forkhead Transcription Factors; D008070:Lipopolysaccharides; D050799:STAT5 Transcription Factor; D050826:Suppressor of Cytokine Signaling Proteins
keywords: Apostichopus japonicus; FOXP; Immune response; JAK/STAT; SOCS2; STAT5