Teo C H, Tan S H, Othman Y R, Schwarzacher T
Department of Biotechnology, Faculty of Food Science and Biotechnology, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
J Biochem Mol Biol Biophys. 2002 Jun;6(3):193-201. doi: 10.1080/10258140290022329.
Ty1-copia-like retrotransposons have been identified and investigated in several plant species. Here, the internal region of the reverse transcriptase (RT) gene of Ty1-copia-like retrotransposons was amplified by PCR from total genomic DNA of 10 varieties of banana. Two to four clones from each variety were sequenced. Extreme heterogeneity in the sequences of Ty1-copia-like retrotransposons from all the varieties was revealed following sequence analysis of the reverse transcriptase (RT) fragments. The size of the individual RT gene fragments varied between 213 and 309 bp. Southern blots of genomic DNA digested from Musa acuminata and other banana varieties probed with W8 clone from M. acuminata and A4 clone from Pisang Abu Nipah showed similar strong, multiple restriction fragments together with other faint hybridization band patterns with variable intensities indicating the presence of many copies of the Ty1-copia-like retrotransposons in the genomes. There was no correlation between retroelement sequence and the banana species (with A or B genomes) from which it arose, suggesting that the probes are not useful for tracking genomes through breeding populations.
已在多种植物物种中鉴定并研究了类Ty1-copia逆转座子。在此，通过PCR从10个香蕉品种的总基因组DNA中扩增了类Ty1-copia逆转座子逆转录酶（RT）基因的内部区域。对每个品种的2至4个克隆进行了测序。对逆转录酶（RT）片段进行序列分析后发现，所有品种的类Ty1-copia逆转座子序列存在极大的异质性。各个RT基因片段的大小在213至309 bp之间变化。用尖叶蕉的W8克隆和马来苹果蕉的A4克隆对尖叶蕉和其他香蕉品种消化后的基因组DNA进行Southern杂交，结果显示出相似的强烈多条限制性片段，以及其他强度各异的微弱杂交带模式，表明基因组中存在许多类Ty1-copia逆转座子拷贝。逆转元件序列与其所源自的香蕉物种（具有A或B基因组）之间没有相关性，这表明这些探针对于通过育种群体追踪基因组并无用处。
