Molecular and evolutionary aspects of self-incompatibility in flowering plants.
Molecular and evolutionary aspects of self-incompatibility in flowering plants.
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开花植物自交不亲和性的分子和进化方面。
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
A. Clarke
中科院分区：
文献类型：
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作者：
S. Mau;M. Anderson;M. Heisler;V. Haring;B. McClure;A. Clarke
自交不亲和性在有花植物中广泛存在。本文就SI的生物学、遗传学和分布等方面的研究进展作一综述。研究表明，在茄科植物中，如烟草阿拉塔（Nicotiana alata）和芸苔属植物（Brassica spp）中，SI的分子遗传学机制存在两个系统：一个是配子体系统，另一个是孢子体系统。这两个系统中的信息来源于编码与S-基因型分离的雌蕊糖蛋白（S-糖蛋白）的cDNA。序列比较表明，SI的配子体系统和孢子体系统可能是在被子植物进化过程中独立出现的。茄科植物烟草（Nicotiana阿拉塔）的S-糖蛋白是核糖核酸酶（RNase）。核糖核酸酶活性是否直接参与自花（不亲和）授粉过程中花粉管生长的特征性停滞，尚不清楚。另一种可能性是RNase在进化过程中被“招募”用于SI中的功能，而不参与其催化功能。花粉中S-基因的性质对于配子体或孢子体SI系统尚不清楚。这是一个关键的信息，将需要我们的理解，如何携带一个特定的S-等位基因的花粉管的生长被逮捕的风格轴承相同的S-等位基因，但不逮捕的风格轴承其他S-等位基因。
Self-incompatibility (SI) is widely distributed in flowering plants. In this review, early work on the biology, genetics and distribution of SI is summarized. Approaches to understanding the molecular genetics of SI have been made in two systems-Solanaceous species, for example Nicotiana alata, which have gametophytic systems of SI, and Brassica spp, which have sporophytic systems of SI. The information in both systems is derived from cDNAs that encode pistil glycoproteins (S-glycoproteins) that segregate with S-genotype. Comparison of the sequence data indicates that the gametophytic and sporophytic systems of SI probably arose independently during the evolution of angiosperms. The S-glycoproteins of a solanaceous plant Nicotiana alata, are ribonucleases (RNases). Whether the RNase activity is directly involved in the characteristic arrest of pollen tube growth during self-(incompatible) pollination, is not known. An alternative possibility is that the RNase was 'recruited' during evolution for a function in SI, without involvement of its catalytic function. The nature of the S-gene in pollen is not yet known for either the gametophytic or sporophytic SI systems. This is a key piece of information that will be required to progress our understanding of how the growth of a pollen tube bearing a particular S-allele is arrested within the style bearing an identical S-allele, but is not arrested within the style bearing other S-alleles.