【摘要】 【目的】阐明养殖密度对西伯利亚杂交鲟（西伯利亚鲟Acipenser baerii♀×施氏鲟Acipenser schrenckii♂）生长性能的影响机制，获得最适宜的养殖密度，为该品种健康养殖提供理论数据。【方法】选取规格一致、健康无病的初始体质量为（7.89±1.45）g的西伯利亚杂交鲟幼鱼，设置低密度组（LD,0.465 kg/m2）、中密度组（MD,0.694 kg/m2）和高密度组（HD,0.930 kg/m2）3个不同的养殖密度进行为期90 d的生产试验，每个密度设置3个重复，每个重复组取1肌肉组织共9个样品进行RNA-seq测序和生物信息学分析。【结果】共得到60.70 Gb Clean Data，各样品的Clean Data均达到6.30 Gb,Q20和Q30碱基百分比在97.45%和93.42%以上；将小体鲟（Acipenser ruthenus）的基因组作为参考基因组进行比对，比对效率在72.64%～74.38%，发掘15 549个新基因；将新基因进行注释发现，12 636个新基因得到注释，2 913个新基因未得到注释；进一步对3个密度组两两比较进行差异表达基因分析，共得到611个非冗余差异表达基因（DEGs），其中LD vs HD和LD vs MD比较组有33个共同DEGs,LD vs HD和MD vs HD比较组有40个共同DEGs,LD vs MD和MD vs HD比较组有31个共同DEGs，只有1个DEG是3个比较组共有；GO功能富集分析发现，这些DEGs主要富集在GTPase活性的增加、肌球蛋白复合物、肌动蛋白结合、ATP结合以及锌离子结合等二级节点中。在此基础上，通过人工筛选与生长应激相关的二级节点，获得了27条与生长应激相关的差异基因，其中包括调控生长轴GH/IGF的生长激素受体（GHR）和胰岛素样生长因子1和2(IGF-1、IGF-2)。选取9条表达差异倍数大的基因进行qRT-PCR验证发现，其mRNA表达趋势均与转录组分析中的表达趋势一致。【结论】不同养殖密度条件下，西伯利亚杂交鲟幼鱼生长、应激等相关基因的表达模式发生显著变化。更多还原

【Abstract】 [Objective]This study aims to clarify the influence mechanism of stocking density on the growth of siberian hybrid sturgeon(Acipenser Baerii ♀× Acipenser Schrenckii ♂)and obtain the optimal stocking density,thus providing theoretical data for the healthy cultivation of the species.[Method]Juvenile siberian hybrid sturgeons with the same specifications and no disease were selected and their initial body weight was(7.89±1.45)g.Low-density group(LD,0.465 kg/m2),medium-density group(MD,0.694 kg/m2)and high-density group(HD,0.930 kg/m2)were used for the production experiment,with three replicate groups set for each density.The experiment period was 90 days.RNA-seq sequencing was performed on the muscle tissues of siberian hybrid sturgeons in different density groups.[Result]A total of 60.70 Gb of clean data were obtained,and the clean data of each sample reached 6.30 Gb,the percentage of Q20 and Q30 base was above 97.45% and 93.42%.The genome of Acipenser ruthenus was used as the reference genome,the comparison efficiency ranged from 72.64%to 74.38%.15 549 new genes were discovered,including 12 636 annotated gens.A total of 611 non-redundant differentially expressed genes(DEGs)were obtained by pin-pin-comparison of the three density groups.Among them,33 common DEGs were found in LD vs. HD and LD vs. MD groups,and 40 common DEGs were found in LD vs. HD and MD vs. HD groups.There were 31 common DEGs in LD vs.MD and MD vs.HD comparison groups,and only 1 DEG was common among the three comparison groups.GO functional enrichment analysis showed that these DEGs were mainly enriched in secondary nodes such as increased GTPase activity,myosin complex,actin binding,ATP binding and zinc ion binding.Based on this,27 differential genes related to growth stress were obtained by artificially screening secondary nodes related to growth stress,among which growth hormone receptor(GHR),insulin-like growth factor 1 and 2(IGF-1,IGF-2)were important members of growth axis GH/IGF.7 differentially expressed genes were selected for qRT-PCR verification,and it was found that mRNA expression trends of nine genes were consistent with those in transcriptome analysis.[Conclusion]The expression patterns of growth,stress and other related genes of juvenile siberian hybrid sturgeon changed significantly under different culture densities.更多还原