Kiss G B, Pearlman R E
Gene. 1981 Apr;13(3):281-7. doi: 10.1016/0378-1119(81)90032-9.
We have determined the restriction-endonuclease-cleavage map and the nucleotide sequence of the central 1.4 kb fragment of the macronuclear extrachromosomal rDNA of Tetrahymena thermophila. These data demonstrate that this molecule is not a perfect palindrome, having a 29 bp AT-rich non-palindromic sequence at its center. This observation is important in determining the mechanism by which a single chromosomally integrated rRNA gene in the micronucleus is rearranged and amplified during sexual development to yield multiple copies of extrachromosomal rDNA in the macronucleus.
我们已经确定了嗜热四膜虫大核染色体外rDNA中央1.4kb片段的限制性内切酶切割图谱和核苷酸序列。这些数据表明,该分子不是一个完美的回文结构,其中心有一个29bp富含AT的非回文序列。这一观察结果对于确定在有性发育过程中,微核中单个染色体整合的rRNA基因如何重排和扩增,从而在大核中产生多个染色体外rDNA拷贝的机制具有重要意义。