The identification and analysis of new members of the tubulin superfamily has advanced the belief that these tubulins play important roles in the duplication and assembly of centrioles and basal bodies. This idea is supported by their distribution in organisms with centrioles containing triplet microtubules and by recent functional analysis of the new tubulins. delta- and epsilon-tubulin are found in most organisms that assemble triplet microtubules. delta-tubulin is needed for maintaining triplet microtubules in Chlamydomonas and Paramecium. epsilon-tubulin is needed for centriole and basal body duplication and is an essential gene in Chlamydomonas. The distribution of eta-tubulin is more limited and has been found in only four organisms to date. Phylogenetic analysis suggests that it is most closely related to delta-tubulin, which suggests that delta- and eta-tubulin could have overlapping functions.

中文翻译：

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失散已久的亲戚重现：微管蛋白超家族新成员的鉴定。

对微管蛋白超家族的新成员的鉴定和分析已使人们相信，这些微管蛋白在中心粒和基体的复制和组装中起着重要作用。它们在具有三重态微管的中心粒中的分布以及最近对新微管蛋白的功能分析支持了这一观点。在组装三重态微管的大多数生物中都发现了δ-和ε-微管蛋白。需要δ-微管蛋白来维持衣藻和草履虫中的三联体微管。ε-微管蛋白是中心体和基体复制所必需的，并且是衣藻中必不可少的基因。eta-微管蛋白的分布较为有限，迄今为止仅在四种生物中发现。系统发育分析表明，它与δ-微管蛋白关系最密切，