期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2001
卷号：98
期号：23
页码：13167-13171
DOI：10.1073/pnas.231386798
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：T2-type RNases are responsible for self-pollen recognition and rejection in three distantly related families of flowering plants--the Solanaceae, Scrophulariaceae, and Rosaceae. We used phylogenetic analyses of 67 T2-type RNases together with information on intron number and position to determine whether the use of RNases for self-incompatibility in these families is homologous or convergent. All methods of phylogenetic reconstruction as well as patterns of variation in intron structure find that all self-incompatibility RNases along with non-S genes from only two taxa form a monophyletic clade. Several lines of evidence suggest that the best interpretation of this pattern is homology of self-incompatibility RNases from the Scrophulariaceae, Solanaceae, and Rosaceae. Because the most recent common ancestor of these three families is the ancestor of {approx}75% of dicot families, our results indicate that RNase-based self-incompatibility was the ancestral state in the majority of dicots.
