对Rett综合征中发现的rRNA基因突变进行计算机辅助的二级结构模拟分析

Computerized ribosomal RNA secondary structrue modeling of mutants found in Rett syndrome patients and their mothers

目的分析Ｒｅｔ综合征中ｒＲＮＡ基因突变ｍｔＤＮＡ２８３５Ｃ→Ｔ和ｍｔＤＮＡ２７０６Ａ→Ｇ引起的ｒＲＮＡ二级结构变化。方法将ｒＲＮＡ基因的野生型和突变后的ｍｔＤＮＡ序列共同输入计算机，以软件ＤＮＡＳＩＳ（６．１４版）加以分析。统一设置模拟长度为３００碱基，最大环径３０碱基。结果ｍｔＤＮＡ２８３５Ｃ→Ｔ与阳性对照一样，使１６ＳｒＲＮＡ二级结构彻底变化，能量变化很大；相反，ｍｔＤＮＡ２７０６Ａ→Ｇ引起的结构和能量变化都很小。结论计算机模拟程序能对这两种突变引起的ｒＲＮＡ结构变化进行快速的预测，其中ｍｔＤＮＡ２８３５Ｃ→Ｔ突变可能与Ｒｅｔ综合征发病有关，而另一个突变ｍｔＤＮＡ２７０６Ａ→Ｇ则对二级结构影响不大。

Objective To identify the secondary structure of rRNA mutants, mtDNA2835CT and mtDNA2706AG found in Rett syndrome patients and their mothers. Methods Both wild type mtDNA sequence of rRNA gene and mutated sequence were input into computer (converted into RNA sequences) and analyzed by the sofware DNASIS v6.14. The unique prediction size is set 300 bases and the maximum bulge and interior loop size, 30 bases. Results Similar to the positive controls, the mtDNA2835CT made the 16S rRNA secondary structure totally different, and the energy changes a lot. On the contrary, the mtDNA2706AG altered little of secondary structure with a small energy shift. Conclusion Computerized folding programs have provided us with a quick prediction of rRNA structure changes induced by these two mutations. Of them, the mtDNA2835CT might relate to the pathogenesis of Rett syndrome, but the mtDNA2706AG might be less meaningful.