鸡七号染色体上的最优密码子

The Optimum Codons of Chromosome 7 in Chicken

研究了鸡七号染色体编码21种氨基酸的密码子的使用情况。研究显示,同义密码子数为2或3的均偏向使用1种密码子(编码TER氨基酸的密码子除外),而同义密码子数为4或6的则有2或3种偏向使用的密码子。由此可以确定,鸡所使用的59种同义密码子中UUC、CUC、ACG、GUG等27个密码子为最优密码子,而且最优密码子均为以C或G结尾的密码子。结果表明,最优密码子的使用与密码子中第3位碱基组成密切相关。

The using condition of codons of chromosome 7 in chicken which code 21 amino acids was studied. Results showed that codons whose number of synonymous codnns was two or three all tended to use one kind of codons except the codons coding TER amino acid, while codons whose number of synonymous codons was four or six tended to use two or three kinds of codons. So it is concluded that among 59 kinds of synonymous codons in chicken, 27 synonymous codons like UUC, CUC, ACG and GUG, etc. were the optimum codons which were all ended by C or G. Thereby, the use of the optimum codons is closely related to the 3^rd base composition.