排序方式: 共有32条查询结果,搜索用时 46 毫秒
31.
Degradation of ribonucleic acid by extracts of germinating peas 总被引:2,自引:0,他引:2
32.
Goldraij A Kondo K Lee CB Hancock CN Sivaguru M Vazquez-Santana S Kim S Phillips TE Cruz-Garcia F McClure B 《Nature》2006,439(7078):805-810
Pollen-pistil interactions are crucial for controlling plant mating. For example, S-RNase-based self-incompatibility prevents inbreeding in diverse angiosperm species. S-RNases are thought to function as specific cytotoxins that inhibit pollen that has an S-haplotype that matches one of those in the pistil. Thus, pollen and pistil factors interact to prevent mating between closely related individuals. Other pistil factors, such as HT-B, 4936-factor and the 120 kDa glycoprotein, are also required for pollen rejection but do not contribute to S-haplotype-specificity per se. Here we show that S-RNase is taken up and sorted to a vacuolar compartment in the pollen tubes. Antibodies to the 120 kDa glycoprotein label the compartment membrane. When the pistil does not express HT-B or 4936-factor, S-RNase remains sequestered, unable to cause rejection. Similarly, in wild-type pistils, compatible pollen tubes degrade HT-B and sequester S-RNase. We suggest that S-RNase trafficking and the stability of HT-B are central to S-specific pollen rejection. 相似文献