Higashiyama T, Noutoshi Y, Akiba M, Yamada T
Department of Fermentation Technology, Faculty of Engineering, Hiroshima University, Japan.
Nucleic Acids Symp Ser. 1995(34):71-2.
The telomeres of Chlorella chromosomes consisted of 5'-TTTAGGG repeats, which are exactly the same as those of higher plants. This sequence was reiterated approximately 70 times at both termini of chromosome I. Subtelomeric sequences next to the telomeres were totally different between the right and left arms. On the left-side subtelomeric region, polyA associated LINE (long interspersed element)-like elements were found tandemly repeated just next to the telomeric repeats. It is very interesting to compare this unique structure with telomeres of Drosophila, where a transposable element play a major role in forming telomerase-generated repeats. We propose a mechanism of transposon-mediated healing of a broken chromosomal end that would operate in the unicellular green alga Chlorella.
小球藻染色体的端粒由5'-TTTAGGG重复序列组成，这与高等植物的端粒完全相同。该序列在染色体I的两端大约重复了70次。端粒旁边的亚端粒序列在右臂和左臂之间完全不同。在左侧亚端粒区域，发现多聚腺苷酸相关的LINE（长散在元件）样元件紧挨着端粒重复序列串联重复。将这种独特结构与果蝇的端粒进行比较非常有趣，在果蝇中，一个转座元件在形成端粒酶产生的重复序列中起主要作用。我们提出了一种转座子介导的断裂染色体末端修复机制，该机制可能在单细胞绿藻小球藻中起作用。
