Matton D. P., Maes O., Laublin G., Xike Q., Bertrand C., Morse D., Cappadocia M.
Institut de Recherche en Biologie Vegetale, Departement de Sciences Biologiques, Universite de Montreal, 4101 rue Sherbrooke est, Montreal, Quebec, Canada H1X 2B2.
Plant Cell. 1997 Oct;9(10):1757-1766. doi: 10.1105/tpc.9.10.1757.
Self-incompatibility (SI) in angiosperms is a genetic mechanism that promotes outcrossing through rejection of self-pollen. In the Solanaceae, SI is determined by a multiallelic S locus whose only known product is an S RNase. S RNases show a characteristic pattern of five conserved and two hypervariable regions. These are thought to be involved in the catalytic function and in allelic specificity, respectively. When the Solanum chacoense S12S14 genotype is transformed with an S11 RNase, the styles of plants expressing significant levels of the transgene reject S11 pollen. A previously characterized S RNase, S13, differs from the S11 RNase by only 10 amino acids, four of which are located in the hypervariable regions. When S12S14 plants were transformed with a chimeric S11 gene in which these four residues were substituted with those present in the S13 RNase, the transgenic plants acquired the S13 phenotype. This result demonstrates that the S RNase hypervariable regions control allelic specificity.
被子植物中的自交不亲和性（SI）是一种遗传机制，通过排斥自身花粉来促进异花授粉。在茄科中，SI由一个多等位基因S位点决定，其唯一已知产物是一种S核糖核酸酶（S RNase）。S RNases呈现出由五个保守区域和两个高变区域组成的特征模式。这些区域分别被认为与催化功能和等位基因特异性有关。当用S11核糖核酸酶转化查科茄（Solanum chacoense）的S12S14基因型时，表达高水平转基因的植株的花柱会排斥S11花粉。一种先前已鉴定的S核糖核酸酶S13与S11核糖核酸酶仅相差10个氨基酸，其中四个位于高变区域。当用嵌合S11基因转化S12S14植株，使这四个残基被S13核糖核酸酶中的残基取代时，转基因植株获得了S13表型。这一结果表明S核糖核酸酶高变区域控制等位基因特异性。
