DNA序列信息的一种新的测度(英文)

A New Measure for DNA Sequence Information

根据信息理论给出了测度ＤＮＡ序列信息的一种新的方法．获得ＤＮＡ序列４个层次的信息量测度：Ｉｂ；Ｉｆ（１），Ｉｆ（２）ａｎｄＩｆ（３）这４种信息测度可分别用来测度ＤＮＡ的碱基序列、密码子序列、编码蛋白质序列和功能蛋白质序列的信息量．从 Ｍ ｅｄｕｌｉｓ的线粒体基因组中两个较短的编码蛋白质的 ＤＮＡ序列和使用具有不同信性的间并密码子组组成的模拟ＤＮＡ序列中所获得计算结果表明，这些信息测度确实能用来揭示所隐含在编码蛋白质的ＤＮＡ中不同层次的有序性．虽然我们还不知道隐含在编码一种蛋白质的ＤＮＡ中各种子序列信息量是否可以反映这种蛋白质的结构与功能的关系，但是有趣的是，这些信息测度可用来比较编码一种同源蛋白的同源ＤＮＡ序列，并且这一ＤＮＡ序列的进化信息．

A new approach to measure information of DNA sequence was given in this paper on the basis of information theory. The parameters of information contents at four levels in DNA sequence were obtained: fo, If(1), If(2), and If(3) which are used to measure information contents of base sequence, codon sequence, protein-coded sequence, functional protein sequence, respectively. The results obtained from the two shorter mtDNA sequences coding for proteins in M. edulis and five stimulated DNA sequences composed of different fold degenerate codon groups showed that our measure for information contents of DNA sequences can, indeed, be used to represent orders hidden at various levels in DNA sequences respectively coding for proteins. Of course, we do not know whether these information contents stored in various subsequences of DNA coding for a protein may reflect relationship between function and structure of the protein. However, it is intersting to use our measures to compare homologous DNA sequences coding for a homologous protein and to reveal evolution information recorded in DNA sequences.