摘要
选择了四个信息参量来刻画核酸序列的进化水平,研究线虫染色体全序列、基因序列和基因间序列的进化水平沿染色体的非均匀分布规律.结果显示各类序列的进化水平沿常染色体呈现明显的非均匀性和规律性.进化水平高的序列分布在染色体的两端,是进化活跃区,进化水平低的序列,分布在染色体的中部,是进化保守区;基因序列和基因间序列是协同进化的,在染色体上具有相同的分布规律;Ⅳ号染色体显示出了染色体形成的拼接模式,由此推断常染色体的形成与进化过程是先以一个进化保守序列为核序列,在其两端拼接其它的序列,通过序列间的协调和融合使之逐渐走向成熟;整个X染色体具有稳定的进化水平,进化模式与常染色体不同.
Based on calculating four information parameters,the evolution levels of different DNA sequences （genes,intergenic sequences and complete sequences） for C. elegans chromosomes are studied. The results show that the evolution levels of each kind of sequences along chromosomes take on obvious heterogeneity and regularity. Sequences with high evolution levels distribute in the two ends of autosomes, which belong to evolutional active regions. Sequences with low evolution levels distribute in the middle part of autosomes, which are evolutional conservative regions. Genes and intergenic sequences take on the same distribution rule, and they are co-evolutional along autosomes. In chromosome Ⅳ ,distributions show the distinct splice mode of chromosome origin. The process of origin and evolution for autosomes is deduced that some needed sequences are added in the two ends of one conservative core sequence. Through coordination and syncretizing by evolutional pressure, the mature chromosome is formed gradually. The X chromosome has not shown the same regulation as autosomes and it takes on stable evolution level. The X chromosome has a different evolution mode.
出处
《内蒙古大学学报（自然科学版）》
CAS
CSCD
北大核心
2006年第5期516-523,共8页
Journal of Inner Mongolia University：Natural Science Edition
基金
国家自然科学基金(10147204)
内蒙古自然科学基金(200508010107)资助项目
关键词
线虫
染色体
信息参量
序列沿染色体排列
进化非均匀性
C. elegans
chromosome
information parameter
sequence array along the chromosome
evolution heterogeneity
