The multiple fates of gene duplications: deletion, hypofunctionalization, subfunctionalization, neofunctionalization, dosage balance constraints, and neutral variation

第一作者：James A Birchler

第一单位：密苏里大学

通讯作者：James A Birchler

 Abstarct 

Gene duplications have long been recognized as a contributor to the evolution of genes with new functions. Multiple copies of genes can result from tandem duplication, from transposition to new chromosomes, or from whole genome duplication (polyploidy). The most common fate is that one member of the pair is deleted to return the gene to the singleton state. Other paths involve the reduced expression of both copies (hypofunctionalization) that are held in duplicate to maintain sufficient quantity of function. The two copies can split functions (subfunctionalization) or can diverge to generate a new function (neofunctionalization). Retention of duplicates resulting from doubling of the whole genome occurs for genes involved with multicomponent interactions such as transcription factors and signal transduction components. In contrast, these classes of genes are underrepresented in small segmental duplications. This complementary pattern suggests that the balance of interactors affects the fate of the duplicate pair. We discuss the different mechanisms that maintain duplicated genes, which may change over time and intersect.

长期以来，基因复制一直被认为是生物演化出具有新功能的基因的驱动力。基因的多个拷贝可能来自串联复制，或是基因转位到新的染色体上，亦或是来自于全基因组复制（多倍化）。基因复制之后最常见的一种情况是，这对基因中的其中一个成员会被从基因组中删除，从而使得基因返回到单拷贝的状态。基因复制之后其它的情况涉及到降低两个基因拷贝的表达（即次功能化），从而需要这两个基因拷贝的同时存在，才能保持原有一个基因拷贝就足够的功能。这两个基因拷贝的功能也可能会发生拆分（即亚功能化），或者发生分化产生一个新的功能（即新功能化）。对于从全基因组复制事件中保存的基因拷贝来说，一般是转录因子和信号转导组分等存在多组分互作的基因。相反，这类基因在小片段的复制事件中保存远远低于预期。这种互补模式表明，互作子的平衡会影响复制基因对的命运。本文中，作者着重讨论了维持复制基因的不同机制，这些机制可能会随着时间的推移而发生变化，并且相互交叉。

** James A Birchler **

doi: https://doi.org/10.1093/plcell/koac076

Journal: The Plant Cell

Published date: March 07, 2022