Multiple LTR-retrotransposon families in the asexual yeast Candida albicans
Multiple LTR-retrotransposon families in the asexual yeast Candida albicans
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DOI：
10.1101/gr.10.2.174
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发表时间：
2000-02-01
期刊：
影响因子：
7
通讯作者：
Poulter, RTM
中科院分区：
文献类型：
--
作者：
Goodwin, TJD;Poulter, RTM
我们已经开始了长末端重复序列（LTR）逆转录转座子在无性酵母白色念珠菌的特性。建立了C.筛选了来自斯坦福大学的白色念珠菌基因组序列，其代表16-Mb单倍体基因组的14.9 Mb，并鉴定了>350个不同的反转录转座子插入。这些插入的大多数代表以前未识别的反转录转座子。各种元素被分为34个不同的家庭，每个家庭是相似的，在它所代表的序列的范围方面，一个典型的Ty元件家族的相关酵母酿酒酵母。这些白色念珠菌逆转录转座子家族通常拷贝数低，编码能力差异很大。只有三个家庭，是一个全长和明显完整的反转录转座子确定。对于许多家族来说，只剩下单独的LTR和LTR片段。几个高度简并的元素家族似乎仍然能够转座，推测是通过反式激活。对C.白色念珠菌与酿酒酵母有很大不同。在那个物种中，反转录转座子插入可以被分配到仅仅五个家族。这些家族中的大多数仍然保留功能性实例，并且它们通常比C.白色念珠菌家族这两个物种之间的这些差异可能归因于C.白念珠菌或其基因组的无性性质进行了讨论。还描述了一个富含反转录转座子片段的区域，该区域与许多CARE-2/Rel-2亚端粒重复序列相邻，并且似乎是通过多轮重复和重组产生的。
We have begun a characterization of the long terminal repeat (LTR) retrotransposons in the asexual yeast Candida albicans. A database of assembled C. albicans genomic sequence at Stanford University, which represents 14.9 Mb of the 16-Mb haploid genome, was screened and >350 distinct retrotransposon insertions were identified. The majority of these insertions represent previously unrecognized retrotransposons. The various elements were classified into 34 distinct families, each family being similar, in terms of the range of sequences that it represents, to a typical Ty element family of the related yeast Saccharomyces cerevisiae. These C, albicans retrotransposon families are generally of low copy number and vary widely in coding capacity. For only three Families, was a full-length and apparently intact retrotransposon identified. For many families, only solo LTRs and LTR Fragments remain. Several families of highly degenerate elements appear to be still capable of transposition, presumably via trans-activation. The over all structure of the retrotransposon population in C. albicans differs considerably from that of S, cerevisiae. In that species, retrotransposon insertions carl be assigned to just five families. Most of these families still retain functional examples, and they generally appear at higher copy numbers than the C. albicans Families. The possibility that these differences between the two species are attributable to the nonstandard genetic code of C. albicans or the asexual nature of its genome is discussed. A region rich in retrotransposon fragments, that lies adjacent to many of the CARE-2/Rel-2 sub-telomeric repeats, and which appears to have arisen through multiple rounds of duplication and recombination, is also described.