Retention of latent centromeres in the mammalian genome
Retention of latent centromeres in the mammalian genome
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DOI：
10.1093/jhered/esi029
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发表时间：
2005-05-01
影响因子：
3.1
通讯作者：
O'Neill, RJ
中科院分区：
文献类型：
--
作者：
Ferreri, GC;Liscinsky, DM;O'Neill, RJ
着丝粒是细胞学定义的实体，在细胞中具有保守和限制的功能：它是动粒组装和纺锤体附着的位点。尽管其保守的功能，着丝粒是染色体的高度可变的部分，携带跨类群的序列保守性很小。这种分歧使得研究着丝粒的运动，无论是在单个核型内还是在物种之间，都是一项具有挑战性的奋进。已经提出了几种假说来解释染色体内着丝粒位置的可置换性。当在进化背景下描述时，这种可置换性被称为“着丝粒重新定位”，当考虑个体核型内的异常时，这种可置换性被称为“新着丝粒化”。两者的特征都是染色体内功能性着丝粒的位置发生变化，而线性基因顺序没有伴随变化。跨谱系的进化研究清楚地表明，着丝粒重新定位不是核型进化中的罕见事件，并且在检查染色体结构和同线顺序的进化时必须考虑。本文探讨了理论提出来解释哺乳动物的着丝粒重新定位。这些理论的解释，在人类研究中获得的证据，并在我们提出的数据从有袋动物的模式物种Macropus eugenii，tammar小袋鼠。
The centromere is a cytologically defined entity that possesses a conserved and restricted function in the cell: it is the site of kinetochore assembly and spindle attachment. Despite its conserved function, the centromere is a highlymutable portion of the chromosome, carrying little sequence conservation across taxa. This divergence has made studying the movement of a centromere, either within a single karyotype or between species, a challenging endeavor. Several hypotheses have been proposed to explain the permutability of centromere location within a chromosome. This permutability is termed "centromere repositioning'' when described in an evolutionary context and "neocentromerization'' when abnormalities within an individual karyotype are considered. Both are characterized by a shift in location of the functional centromere within a chromosome without a concomitant change in linear gene order. Evolutionary studies across lineages clearly indicate that centromere repositioning is not a rare eventin karyotypic evolution and must be considered when examining the evolution of chromosome structure and syntenic order. This paper examines the theories proposed to explain centromere repositioning in mammals. These theories are interpreted in light of evidence gained in human studies and in our presented datafrom the marsupial model species Macropus eugenii, the tammar wallaby.