Wuyts J, De Rijk P, Van de Peer Y, Pison G, Rousseeuw P, De Wachter R
Departement Biochemie, Universiteit Antwerpen (UIA), Universiteitsplein 1, B 2610 Antwerpen, Belgium.
Nucleic Acids Res. 2000 Dec 1;28(23):4698-708. doi: 10.1093/nar/28.23.4698.
The secondary structure of V4, the largest variable area of eukaryotic small subunit ribosomal RNA, was re-examined by comparative analysis of 3253 nucleotide sequences distributed over the animal, plant and fungal kingdoms and a diverse set of protist taxa. An extensive search for compensating base pair substitutions and for base covariation revealed that in most eukaryotes the secondary structure of the area consists of 11 helices and includes two pseudoknots. In one of the pseudoknots, exchange of base pairs between the two stems seems to occur, and covariation analysis points to the presence of a base triple. The area also contains three potential insertion points where additional hairpins or branched structures are present in a number of taxa scattered throughout the eukaryotic domain.
真核生物小亚基核糖体RNA最大可变区V4的二级结构，通过对分布于动物、植物和真菌界以及各种原生生物类群的3253个核苷酸序列进行比较分析，得以重新审视。广泛搜索补偿性碱基对替换和碱基共变现象发现，在大多数真核生物中，该区域的二级结构由11个螺旋组成，包括两个假结。在其中一个假结中，两个茎之间似乎发生了碱基对交换，共变分析表明存在一个碱基三联体。该区域还包含三个潜在的插入点，在真核生物域中分散的许多类群中存在额外的发夹或分支结构。
