The Reaserch Of Protosalanx Hyalocranius Embryo’s Molecular Adaption Mechanism To Salt Stress Based On Transcriptome Sequencing Technology

[Objection] At present, the research survival mechanism for fish in different salinity environments has mainly focused on the maturity, which is very little for embryo, the origin of life. This paper selects representative species of estuarine fishes, Protosalanx Hyalocranius, as a study object, from the perspective of genomes for the first time, to explorer the molecular mechanism under the salt stress and the osmotic regulation gene features of Protosalanx hHyalocranius embryos, establishing a theoretical foundation for the osmosis regulation to adapt to environment, and have important scientific significance to understand the species survival and distribution pattern.[Method] Protosalanx Hyalocranius embryos with biological activity are randomly divided into two groups which are control group (freshwater) and low-salt group (15%o saline). Each group set up three groups in parallel as follow:control group1(ctrl-1), control group2(ctrl-2) and control group3(ctrl-3); salt treatment group1(salt-1), salt treatment group2(salt-2) and salt treatment group3(salt-3). All the embryos will be incubated completely in the same conditions. The second generation of gene sequencing technology will be used to sequence the embryos’transcriptome, getting the genetic details according to Phrap algorithm based on the BLAST and GO-Term Finder software. Based on the data analysis, target genes to be selected。The Real-Time PCR technology is adopted to research the target genes, revealing the genome regulating mechanism.[Results]1. According to the statistics of embryos sequencing, the Total Clean Nucleotides in the control group is473×107nt, which is456×107nt in the low salinity treatment group.100600unigenes are acquired by gene splicing,60129of them are annotated in Nr. Coding sequence (CDS) is predicted to be62,434. According to the Nr annotation, the homologous species of Protosalanx Hyalocranius are as follow, Tilapia, Zebrafish, and Medaka.2. The relative target gene’s annotation detail of Protosalanx Hyalocranius embryos is acquired for the first time. The result shows that, the salt stress can make embryo NKA(P<0.01), NKCC, AQP8, Hsp70increased significantly (P<0.05), respectively increased by4.6,3.7,4.3and3.1times. The salt stress also make Kir decreased significantly (P<0.05) by39%. Other genes involved in salt osmotic regulation also change with no significance in statistical yet.[Conclusion] The experiment shows that under the stress of salt water, the expression level of target genes involved in salt osmotic regulation from Protosalanx Hyalocranius embryos can be changed significantly, which means the these changes can be involved in the osmotic regulation. Their influencing mechanism is related to the role of Na+channel, the H+channels and K+channel, their significantly changes are likely to constitute the molecular basis of Protosalanx Hyalocranius wide adaptability to salinity. According to the existing genome database, we also found that the relativity gene between Tilapia Mossambica and Protosalanx Hyalocranius, which means that these species may be have kinship.