title: The evolution of angiosperm seed proteins: a methionine-rich legumin subfamily present in lower angiosperm clades.
abstract: 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.
authors.affiliation: Lehrstuhl für Pflanzenökologie und Systematik, Universität Bayreuth, Universitätsstr. 30, D-95440 Bayreuth, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Fischer
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.forename: S
authors.initials: S
authors.lastname: Wallisch
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D018076:DNA, Complementary; D019143:Evolution, Molecular; D008715:Methionine / Q000032:analysis*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry*; D010944:Plants / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D018749:RNA, Plant / Q000032:analysis; D012639:Seeds / Q000737:chemistry*; D016415:Sequence Alignment; D000097793:Legumins
chemical_list: D000596:Amino Acids; D018076:DNA, Complementary; D008715:Methionine; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D000097793:Legumins