Centromeres pose an evolutionary paradox: strongly conserved in function but rapidly changing in sequence and structure. However, in the absence of damage, centromere locations are usually conserved within a species. We report here that isolates of the pathogenic yeast species Candida parapsilosis show within-species polymorphism for the location of centromeres on two of its eight chromosomes. Its old centromeres have an inverted-repeat (IR) structure, whereas its new centromeres have no obvious structural features but are located within 30 kb of the old site. Centromeres can therefore move naturally from one chromosomal site to another, apparently spontaneously and in the absence of any significant changes in DNA sequence. Our observations are consistent with a model in which all centromeres are genetically determined, such as by the presence of short or long IRs or by the ability to form cruciforms. We also find that centromeres have been hotspots for genomic rearrangements in the C. parapsilosis clade.

中文翻译：

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致病性酵母假丝酵母中的多态性着丝粒位置。

着丝粒构成进化悖论：功能上非常保守，但序列和结构却迅速变化。但是，在没有损害的情况下，着丝粒的位置通常在一个物种内是保守的。我们在这里报告，病原酵母种假丝酵母的分离株显示出其八个染色体中的两个上的着丝粒位置的种内多态性。它的旧着丝粒具有反向重复（IR）结构，而它的新着丝粒没有明显的结构特征，但位于旧位点的30 kb之内。因此，着丝粒可以自然地从一个染色体位点自然地移动到另一个染色体位点，并且在DNA序列中没有任何显着变化。我们的观察结果与通过遗传确定所有着丝粒的模型一致，例如由于存在短或长的IR或形成十字形的能力。我们还发现，着丝粒一直是C. parapsilosis进化枝中基因组重排的热点。