ENU诱变草鱼家系生长特性及肌肉生长抑制素基因SNP筛选的研究

经过175 d养殖,对4个N-乙基-N-亚硝基脲(ENU)诱变草鱼家系进行生长对比,采用显著性比较,偏相关分析和因子分析统计方法对草鱼体质量、全长、体长、头长、体高、尾柄长、尾柄高、体厚性状进行分析,进而运用双向测序法对MSTN1、MSTN2基因在具有明显差异家系中进行SNP位点筛选。试验结果显示,家系4的生长速度明显大于家系3,家系4的8个性状明显大于其他3个家系;家系1中体长、尾柄长、体厚与体质量密切相关,家系2中体长、头长、体厚与体质量密切相关,家系3中全长、体长、尾柄高与体质量密切相关,家系4中全长、体长、体厚与体质量密切相关。由此可知,家系4和家系3具有明显的生长差异。对于MSTN1基因,家系3在465位点C/G、467位点G/A,家系4在465位点C/G均发生错义突变;对于MSTN2基因,家系3和4在912位点C/T均发生同义突变,家系3在1027位点G/A、家系4在366位点A/G均产生错义突变,位于非编码区1390位点A/T和1401位点G/A在两个家系均发现SNP位点。试验结果表明,MSTN1、MSTN2基因的不同SNP位点与ENU诱变草鱼的生长性状存在紧密联系。

Growth and Single Nucleotide Polymorphism Loci Analysis of Myostatin Gene in ENU Mutagenesis Grass Carp Family

Juveniles of mutagenesis grass carp(Ctenopharyngodon idellus) by N-ethyl-N-nitrosourea(ENU) in four families were reared in a 6 m × 4 m × 1.5 m cement pond for 175 days to compare the growth. Significant comparisons, partial correlation analysis, and factor analysis statistical methods were used to analyze body weight, total length, body length, head length, body depth, caudal peduncle length, caudal peduncle height, and body width and single nucleotide polymorphism(SNP) loci of myostatin(MSTN) gene MSTN1 and MSTN2 genes in families with significant differences screened by two-way sequencing. There was significantly better growth in family 4 than that in family 3, with significantly higher 8 characters in family 4 than in the other families(P<0.05). The partial correlation analysis of the relationship between the morphological traits and body weight indicated that there were correlation coefficient of 0.357 between total length and body weight, 0.619 between body length and body weight, 0.608 between caudal peduncle length and body weight, and 0.396 between body width and body weight in family 1;there were correlation coefficient of 0.348 between total length and body weight, 0.360 between body length and body weight, 0.687 between head length and body weight, and-0.384 between body width and body weight in family 2;in family 3 there were correlation coefficient of 0.529 total length, 0.449 body length,-0.351 caudal peduncle length, and 0.384 caudal peduncle height;and in family 4 there were 0.629 total length, 0.543 body length, and 0.590 body width, showing the significat difference in growth between family 4 and family 3. For MSTN1, 465 nt C/G and 467 nt G/A in family 3, and 465 nt C/G in family 4 were found missense mutations;For MSTN2, 912 nt C/T in family 3 and family 4 was found synonymous mutation, 1027 nt G/A in family 3,and 366 nt A/G and in family 4 were found missense mutations, and SNP sites were found in both noncoding regions 1390 nt A/T and 1401 nt G/A in both families. The findings indicate that the SNPs of MSTN1 and MSTN2 genes are closely related to the growth traits of ENU mutagenesis grass carp.