title: An oyster species-specific miRNA scaffold42648_5080 modulates haemocyte migration by targeting integrin pathway.
abstract: miRNAs are important gene regulators at post-transcriptional level and can modulate diverse biological processes, including immune response. Dozens of species-specific miRNAs have been identified in oyster Crassostrea gigas while their functions remain largely unknown. In the present study, an oyster species-specific miRNA scaffold42648_5080 was found responsive to LPS stimulation and might target a total of 31 oyster genes possibly involved in cell communication, cellular localization and cellular response to stimulus. Besides, in gain-of-function assay of scaffold42648_5080 in vivo, the phagocytosis (30.90% in miRNA group verse 23.20% in miRNA control group), apoptosis (3.10% in miRNA group verse 5.30% in miRNA control group) and migration rate (13.88% in miRNA group verse 21.03% in miRNA control group) of oyster haemocytes were found significantly altered after the injection of scaffold42648_5080 mimics. Among the target genes, integrin-linked kinase (CgILK) was considered crucial in cell migration and its interaction with scaffold42648_5080 was then verified both in vitro and in vivo. Consequently, a significant decrease of relative luciferase ratio was observed in CgILK 3'-UTR luciferase reporter assay after transfection of scaffold42648_5080 mimics (0.70-fold of that in blank group, p < 0.01). Meanwhile, when scaffold42648_5080 was overexpressed in vivo (5.41-fold of miRNA control group, p < 0.01), the expression of CgILK declined significantly to 0.25-fold of miRNA control group (p < 0.01). Comparatively, a significant decrease of the haemocyte migration rate (19.76% verse 34.82% in siEGFP control group, p < 0.01) was observed after knock-down of CgILK in vivo. The present study, as far as we know, for the first time revealed the immunomodulation role of an oyster species-specific miRNA, which might provide new insights into miRNA-mediated adaptation mechanism of oysters.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China. Electronic address: haowang@qdio.ac.cn.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Jiachao
authors.initials: J
authors.lastname: Xu
authors.affiliation: Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, 116023, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
authors.forename: Limei
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, 116023, China. Electronic address: lshsong@dlou.edu.cn.
authors.forename: Linsheng
authors.initials: L
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002465:Cell Movement; D003001:Cloning, Molecular; D049896:Crassostrea / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D006434:Hemocytes / Q000378:metabolism*; D007111:Immunity, Cellular; D016023:Integrins / Q000378:metabolism; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D016023:Integrins; D035683:MicroRNAs; D012333:RNA, Messenger
keywords: Cell migration; Cellular immune response; Integrin pathway; Integrin-linked kinase; Species-specific miRNA