title: Functional diversification of MYB23 and GL1 genes in trichome morphogenesis and initiation.
abstract: The functional diversification of duplicated genes is one of the driving forces in evolution. To understand the molecular mechanisms of gene diversification, we studied the functional relationship of the two Arabidopsis paralogous MYB-related genes GL1 and MYB23. We show that MYB23 controls trichome branching and trichome initiation at leaf edges. The latter is controlled redundantly together with GL1. We show that the two proteins are functionally equivalent during trichome initiation but not during trichome branching. RT-PCR and reporter construct analysis revealed spatial, temporal and genetic differences in transcriptional regulation of the GL1 and MYB23 genes. Presented data indicate that the diversification of GL1 and MYB23 gene functions occurred at the level of cis-regulatory sequences with respect to trichome initiation, and that, in parallel, the diversification with respect to regulation of trichome branching also involved changes in respective proteins.
authors.affiliation: Botanical Institute, University of Cologne, Gyrhofstrasse 15, 50931 Cologne, Germany.
authors.forename: Victor
authors.initials: V
authors.lastname: Kirik
authors.forename: Myeong Min
authors.initials: MM
authors.lastname: Lee
authors.forename: Katja
authors.initials: K
authors.lastname: Wester
authors.forename: Ullrich
authors.initials: U
authors.lastname: Herrmann
authors.forename: Zhengui
authors.initials: Z
authors.lastname: Zheng
authors.forename: David
authors.initials: D
authors.lastname: Oppenheimer
authors.forename: John
authors.initials: J
authors.lastname: Schiefelbein
authors.forename: Martin
authors.initials: M
authors.lastname: Hulskamp
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D005786:Gene Expression Regulation / Q000502:physiology; D009154:Mutation; D018515:Plant Leaves / Q000254:growth & development / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics* / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C500589:Myb protein, Arabidopsis; D014157:Transcription Factors; C071556:GL1 protein, Arabidopsis