GORDITA (AGL63) is a young paralog of the Arabidopsis thaliana B(sister) MADS box gene ABS (TT16) that has undergone neofunctionalization.

TY - JOUR

T1 - GORDITA (AGL63) is a young paralog of the Arabidopsis thaliana B(sister) MADS box gene ABS (TT16) that has undergone neofunctionalization.

AU - Erdmann, Robert

AU - Gramzow, Lydia

AU - Melzer, Rainer

AU - Theissen, Günter

AU - Becker, Annette

PY - 2010

Y1 - 2010

N2 - MIKC-type MADS domain proteins are key regulators of flower development in angiosperms. B(sister) genes constitute a clade with a close relationship to class B floral homeotic genes, and have been conserved for more than 300 million years. The loss-of-function phenotype of the A. thaliana B(sister) gene ABS is mild: mutants show reduced seed coloration and defects in endothelium development. This study focuses on GORDITA (GOA, formerly known as AGL63), the most closely related paralog of ABS in A. thaliana, which is thought to act redundantly with ABS. Phylogenetic trees reveal that the duplication leading to ABS and GOA occurred during diversification of the Brassicaceae, and further analyses show that GOA has evolved under relaxed selection pressure. The knockdown phenotype of GOA suggests a role for this gene in fruit longitudinal growth, while over-expression of GOA results in disorganized floral structure and addition of carpel-like features to sepals. Given the phylogeny and function of other B(sister) genes, our data suggest that GOA has evolved a new function as compared to ABS. Protein analysis reveals that the GOA-specific 'deviant' domain is required for protein dimerization, in contrast to other MIKC-type proteins that require the K domain for dimerization. Moreover, no shared protein interaction partners for ABS and GOA could be identified. Our experiments indicate that modification of a protein domain and a shift in expression pattern can lead to a novel gene function in a relatively short time, and highlight the molecular mechanism by which neofunctionalization following gene duplication can be achieved.

AB - MIKC-type MADS domain proteins are key regulators of flower development in angiosperms. B(sister) genes constitute a clade with a close relationship to class B floral homeotic genes, and have been conserved for more than 300 million years. The loss-of-function phenotype of the A. thaliana B(sister) gene ABS is mild: mutants show reduced seed coloration and defects in endothelium development. This study focuses on GORDITA (GOA, formerly known as AGL63), the most closely related paralog of ABS in A. thaliana, which is thought to act redundantly with ABS. Phylogenetic trees reveal that the duplication leading to ABS and GOA occurred during diversification of the Brassicaceae, and further analyses show that GOA has evolved under relaxed selection pressure. The knockdown phenotype of GOA suggests a role for this gene in fruit longitudinal growth, while over-expression of GOA results in disorganized floral structure and addition of carpel-like features to sepals. Given the phylogeny and function of other B(sister) genes, our data suggest that GOA has evolved a new function as compared to ABS. Protein analysis reveals that the GOA-specific 'deviant' domain is required for protein dimerization, in contrast to other MIKC-type proteins that require the K domain for dimerization. Moreover, no shared protein interaction partners for ABS and GOA could be identified. Our experiments indicate that modification of a protein domain and a shift in expression pattern can lead to a novel gene function in a relatively short time, and highlight the molecular mechanism by which neofunctionalization following gene duplication can be achieved.

KW - Phylogeny

KW - Polymerase Chain Reaction

KW - Electrophoretic Mobility Shift Assay

KW - Arabidopsis/genetics/metabolism

KW - Arabidopsis Proteins/genetics/metabolism

KW - Gene Expression Regulation, Plant/genetics/physiology

KW - MADS Domain Proteins/genetics/metabolism

KW - Plants, Genetically Modified/genetics/metabolism

KW - Transformation, Genetic

KW - Phylogeny

KW - Polymerase Chain Reaction

KW - Electrophoretic Mobility Shift Assay

KW - Arabidopsis/genetics/metabolism

KW - Arabidopsis Proteins/genetics/metabolism

KW - Gene Expression Regulation, Plant/genetics/physiology

KW - MADS Domain Proteins/genetics/metabolism

KW - Plants, Genetically Modified/genetics/metabolism

KW - Transformation, Genetic

M3 - SCORING: Journal article

VL - 63

SP - 914

EP - 924

JO - PLANT J

JF - PLANT J

SN - 0960-7412

IS - 6

M1 - 6

ER -