Wheeler M J, Armstrong S A, Franklin-Tong V E, Franklin F C H
Wolfson Laboratory for Plant Molecular Biology, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
J Exp Bot. 2003 Jan;54(380):131-9. doi: 10.1093/jxb/erg006.
The self-incompatibility (SI) response in Papaver rhoeas depends upon the cognate interaction between a pollen-expressed receptor and a stigmatically expressed ligand. The genes encoding these components are situated within the S-locus. In order for SI to be maintained, the genes encoded by the S-locus must be co-inherited with no recombination between them. Several hypotheses, including sequence heterogeneity and chromosomal position, have been put forward to explain the maintenance of the S-locus in the SI systems of the Brassicaceae and the Solanaceae. A region of the Papaver rhoeas genome encompassing part of the self-incompatibility S(1) locus has been cloned and sequenced. The clone contains the gene encoding the stigmatic component of the response, but does not contain a putative pollen S-gene. The sequence surrounding the S(1) gene contains several diverse repetitive DNA elements. As such, the P. rhoeas S-locus bears similarities to the S-loci of other SI systems. An attempt to localize the P. rhoeas S-locus using fluorescence in situ hybridization (FISH) has also been made. The potential relevance of the findings to mechanisms of recombination suppression is discussed.
虞美人中的自交不亲和（SI）反应取决于花粉表达的受体与柱头表达的配体之间的同源相互作用。编码这些成分的基因位于S位点内。为了维持自交不亲和，S位点编码的基因必须共同遗传，且它们之间不能发生重组。已经提出了几种假说，包括序列异质性和染色体位置，以解释十字花科和茄科SI系统中S位点的维持。虞美人基因组中包含部分自交不亲和S(1)位点的区域已被克隆和测序。该克隆包含编码反应柱头成分的基因，但不包含假定的花粉S基因。S(1)基因周围的序列包含几个不同的重复DNA元件。因此，虞美人的S位点与其他SI系统的S位点有相似之处。也有人尝试使用荧光原位杂交（FISH）来定位虞美人的S位点。讨论了这些发现与重组抑制机制的潜在相关性。
