STRUCTURE OF TRANSFER-RNA MOLECULES CONTAINING LONG VARIABLE LOOP
STRUCTURE OF TRANSFER-RNA MOLECULES CONTAINING LONG VARIABLE LOOP
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DOI：
10.1093/nar/3.11.3235
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发表时间：
1976-01-01
影响因子：
14.9
通讯作者：
SUNDARALINGAM, M
中科院分区：
文献类型：
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作者：
BRENNAN, T;SUNDARALINGAM, M
提出了一种结构的II型tRNA分子含有长的可变环和三级碱基的相互作用，在这里进行了比较与I型tRNA具有短的可变环。II型tRNA在它们的三级碱基配对相互作用方面与I型tRNA相似，但与它们的区别通常在于没有三级碱基三联体。长可变环由螺旋茎和末端的环组成，从二氢尿苷螺旋的深沟侧出现，并与酵母tRNAPhe中发现的氨基酸-假尿苷和反密码子-二氢尿苷螺旋形成的平面倾斜约30°。事实上，许多I型tRNA也缺乏完整的碱基三联体，这表明三级碱基对可能足以维持其生物学功能所需的tRNA折叠。基本三元组和变量循环似乎没有什么功能意义。第9位的碱基类型与二氢尿苷茎中的碱基三联体和G-C碱基对的数量相关。
A structure is proposed for the type II tRNA molecules containing the long variable loop and the tertiary base interactions here are compared with type I tRNAs having the short variable loop. The type II tRNAs are similar to the type I tRNAs in their tertiary base pairing interactions but differ from them generally by not having the tertiary base triples. The long variable loop, which is comprised of a helical stem and a loop at the end of it, emerges from the deep groove side of the dihydrouridine helix, and is tilted roughly 30° to the plane formed by the amino acid-pseudouridine and anticodon-dihydrouridine helices found in yeast tRNAPhe. The fact that many of the type I tRNAs also lack the full compliment of base triples suggests that the tertiary base pairs may alone suffice to sustain the tRNA fold required for its biological function. The base triples and the variable loop appear to have little functional significance. The base type at position 9 is correlated with the number of base triples and G-C base pairs in the dihydrouridine stem.