Appearance and elaboration of the XXXX receptor family during land plant evolution.

@entity71521 @entity69021 @entity958 @entity3793 @entity17573 @entity71520 @entity63190 @entity58381 @entity71519 @entity1786
UNASSIGNED: @entity1786 is perceived following binding to endoplasmic reticulum-localized receptors, which in @entity958 , include @entity58381 , @entity71519 , @entity63190 , @entity71520 , and @entity71521 . These receptors fall into two subfamilies based on conservation of features within their @entity3793 kinase domain. Subfamily 1 contains @entity58381 and @entity71519 whereas subfamily 2 contains @entity63190 , @entity71520 , and @entity71521 . Because @entity1786 receptors are found only in plants, this raises questions of when each receptor evolved. Here it is shown that subfamily 1 receptors encoded by a multigene family are present in all charophytes examined, these being most homologous to @entity58381 based on their evolutionary relationship as well as containing @entity3793 kinase and receiver domains. In charophytes and @entity17573 , one or more gene family members contain the intron characteristic of subfamily 2 genes, indicating the first step in subfamily 2 receptor evolution. @entity71519 homologs appear in basal angiosperm species after @entity69021 and, in some early and basal angiosperm species and monocots in general, it is the only subfamily 1 receptor present. Distinct @entity63190 and @entity71520 homologs appear only in core eudicots and @entity71521 homologs appear only in the Brassicaceae, suggesting it is the most recent receptor to evolve. These findings show that a subfamily 1 receptor had evolved and a subfamily 2 receptor had begun to evolve in plants prior to the colonization of land and only these two existed up to the appearance of the first basal angiosperm. The appearance of @entity71521 in the Brassicaceae suggests ongoing evolution of the @entity1786 receptor family.
