Open AccessPlant Expansins Are a Complex Multigene Family with an Ancient Evolutionary Origin
Author(s) -
Yang Li,
Catherine P. Darley,
Verónica Ongaro,
Andrew J. Fleming,
Ori Schipper,
Sandra L. Baldauf,
Simon J. McQueenMason
Publication year - 2002
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.010658
Subject(s) - expansin , biology , physcomitrella patens , arabidopsis , phylogenetic tree , fern , genome , botany , phylogenetics , evolutionary biology , bryopsida , gene , genetics , gene expression , mutant
Expansins are a group of extracellular proteins that directly modify the mechanical properties of plant cell walls, leading to turgor-driven cell extension. Within the completely sequenced Arabidopsis genome, we identified 38 expansin sequences that fall into three discrete subfamilies. Based on phylogenetic analysis and shared intron patterns, we propose a new, systematic nomenclature of Arabidopsis expansins. Further phylogenetic analysis, including expansin sequences found here in monocots, pine (Pinus radiata, Pinus taeda), fern (Regnellidium diphyllum, Marsilea quadrifolia), and moss (Physcomitrella patens) indicate that the three plant expansin subfamilies arose and began diversifying very early in, if not before, colonization of land by plants. Closely related "expansin-like" sequences were also identified in the social amoeba, Dictyostelium discoidium, suggesting that these wall-modifying proteins have a very deep evolutionary origin.