Cryptons: a group of tyrosine-recombinase-encoding DNA transposons from pathogenic fungi
Cryptons: a group of tyrosine-recombinase-encoding DNA transposons from pathogenic fungi
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DOI：
10.1099/mic.0.26529-0
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发表时间：
2003-11-01
期刊：
影响因子：
2.8
通讯作者：
Poulter, RTM
中科院分区：
文献类型：
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作者：
Goodwin, TJD;Butler, MI;Poulter, RTM
在几种致病真菌中检测到一组新的转座因子，作者将其命名为cryptons，包括担子菌新型隐球菌、子囊菌球孢子菌和荚膜组织胞浆菌。这些元件不同于任何先前描述的转座子。该组的原型成员密码子Cn 1长度为4kb，并且以低但可变的拷贝数存在于多种C. neoformans菌株。它显示其插入位点的菌株间变异，表明最近的流动性。内部区域包含一个长基因，被几个内含子打断。该基因的产物在其中部附近含有一个假定的酪氨酸重组酶，在其C-末端附近含有一个与几种真菌转录因子的DNA结合结构域序列相似的区域。该元件不含长重复序列，但与短的同向重复序列相邻，该短的同向重复序列可能是通过重组插入宿主基因组而产生的。密码子Cn 1的许多结构特征在其他已知密码子中是保守的，这表明这些元件代表了功能形式。子囊菌和担子菌中存在的隐子表明这是一组古老的元素（> 4亿年）。序列比较表明，密码子可能与酪氨酸重组酶编码逆转录转座子的DIRS 1和Ngaro 1组有关。
A new group of transposable elements, which the authors have named cryptons, was detected in several pathogenic fungi, including the basidiomycete Cryptococcus neoformans, and the ascomycetes Coccidioides posadasii and Histoplasma capsulatum. These elements are unlike any previously described transposons. An archetypal member of the group, crypton Cn1, is 4 kb in length and is present at a low but variable copy number in a variety of C. neoformans strains. It displays interstrain variations in its insertion sites, suggesting recent mobility. The internal region contains a long gene, interrupted by several introns. The product of this gene contains a putative tyrosine recombinase near its middle, and a region similar in sequence to the DNA-binding domains of several fungal transcription factors near its C-terminus. The element contains no long repeat sequences, but is bordered by short direct repeats which may have been produced by its insertion into the host genome by recombination. Many of the structural features of crypton Cn1 are conserved in the other known cryptons, suggesting that these elements represent the functional forms. The presence of cryptons in ascomycetes and basidiomycetes suggests that this is an ancient group of elements (>400 million years old). Sequence comparisons suggest that cryptons may be related to the DIRS1 and Ngaro1 groups of tyrosine-recombinase-encoding retrotransposons.