Ontophyletics of the nervous system: eyeless mutants illustrate how ontogenetic buffer mechanisms channel evolution.
Ontophyletics of the nervous system: eyeless mutants illustrate how ontogenetic buffer mechanisms channel evolution.
复制标题
神经系统的本体发育学：无眼突变体说明了本体发育缓冲机制如何引导进化。
DOI：
10.1073/pnas.78.1.397
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发表时间：
1981
影响因子：
11.1
通讯作者：
Kaiserman-Abramof,IR
中科院分区：
文献类型：
--
作者：
Katz,MJ;Lasek,RJ;Kaiserman-Abramof,IR
遗传学和分子生物学已经揭示了基因组在系统发育中一代又一代提供连续性和变异的机制。胚胎学和发育生物学揭示了将基因组转变为有机体的机制。突变是进化变化的基础，其本身并不能确保其产物与未改变基因的产物之间的一致性。因此，突变不一定会产生可行的生物体。另一方面，个体发生缓冲机制通常在发育中的生物体中保持一致性。此外，个体发生缓冲机制可以将不一致的突变整合到可存活的有机体中，然后在进化过程中得以延续。一种个体发生缓冲机制（代偿性神经支配）的进化作用在无眼突变小鼠中得到了很好的说明。在无眼小鼠中，单个基因突变去除了背外侧膝状核的传入轴突，而另一组轴突的代偿性神经支配确保了背外侧膝状体仍然整合到中枢神经系统中。在每个生物体的个体发育中，都有一个补偿性神经支配来源的层次结构，这个层次结构将决定如何缓冲任何特定的传入神经阻滞突变。通过这种方式，个体发育可以引导它所属的系统发育。
Genetics and molecular biology have shown the mechanisms that allow the genome to provide both the continuity and the variation from generation to generation within a phylogeny. Embryology and developmental biology show the mechanisms that turn the genome into an organism. Mutations, the basis for evolutionary change, cannot in themselves ensure concordance between their products and the products of unchanged genes. Thus, mutations will not necessarily produce a viable organism. On the other hand, ontogenetic buffer mechanisms normally maintain concordance in the developing organism. In addition, ontogenetic buffer mechanisms can integrate discordant mutations into viable organisms that can then be perpetuated during evolution. The evolutionary role of one ontogenetic buffer mechanism, compensatory innervation, is well illustrated in the anopthalmic mutant mouse. In the anopthalmic mouse, a single gene mutation removes afferent axons of the dorsal lateral geniculate nucleus, and compensatory innervation by another population of axons ensures that the dorsal lateral geniculate remains integrated into the central nervous system. Within each organism's ontogeny is a hierarchy of sources of compensatory innervation, and this hierarchy will determine how any particular deafferentating mutation will be buffered. In this way, an ontogeny can channel the phylogeny of which it is a member.