Fischer H, Chen L, Wallisch S
Lehrstuhl für Pflanzenökologie und Systematik, Universität Bayreuth, Universitätsstr. 30, D-95440 Bayreuth, Germany.
J Mol Evol. 1996 Oct;43(4):399-404. doi: 10.1007/BF02339013.
Analysis of legumin-encoding cDNAs from Dioscorea caucasica Lipsky (Dioscoreaceae) and from Asarum europaeum L. (Aristolochiaceae) shows that there is an especially methionine-rich legumin subfamily present in the lower angiosperm clades including the Monocotyledoneae. It is characterized by a methionine content of 3-4 mol% which is roughly triple the methionine proportion of most other legumins. These "MetR" legumins, if present, still have to be detected in the higher angiosperms including the important seed crops. Evolutionary analysis suggests that the MetR legumins are the result of a gene duplication allowing the differentiation of legumin genes according to their sulfur content. The duplication event must have taken place before the split into mono- and dicotyledonous plants but probably after the separation of angiosperms and gymnosperms.
对高加索薯蓣（薯蓣科）和欧洲细辛（马兜铃科）中豆球蛋白编码cDNA的分析表明，在包括单子叶植物在内的低等被子植物分支中存在一个特别富含甲硫氨酸的豆球蛋白亚家族。其特征在于甲硫氨酸含量为3 - 4摩尔%，这大约是大多数其他豆球蛋白中甲硫氨酸比例的三倍。这些“MetR”豆球蛋白（如果存在的话）仍有待在包括重要种子作物在内的高等被子植物中检测到。进化分析表明，MetR豆球蛋白是基因复制的结果，这使得豆球蛋白基因能够根据其硫含量进行分化。复制事件肯定发生在被子植物分为单子叶植物和双子叶植物之前，但可能发生在被子植物和裸子植物分离之后。
