Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Genetics. 2005 Apr;169(4):2209-23. Epub 2005 Jan 31.

The evolution of the SEPALLATA subfamily of MADS-box genes: a preangiosperm origin with multiple duplications throughout angiosperm history.

Author information

  • 1Department of Biology, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, 16802, USA.

Abstract

Members of the SEPALLATA (SEP) MADS-box subfamily are required for specifying the "floral state" by contributing to floral organ and meristem identity. SEP genes have not been detected in gymnosperms and seem to have originated since the lineage leading to extant angiosperms diverged from extant gymnosperms. Therefore, both functional and evolutionary studies suggest that SEP genes may have been critical for the origin of the flower. To gain insights into the evolution of SEP genes, we isolated nine genes from plants that occupy phylogenetically important positions. Phylogenetic analyses of SEP sequences show that several gene duplications occurred during the evolution of this subfamily, providing potential opportunities for functional divergence. The first duplication occurred prior to the origin of the extant angiosperms, resulting in the AGL2/3/4 and AGL9 clades. Subsequent duplications occurred within these clades in the eudicots and monocots. The timing of the first SEP duplication approximately coincides with duplications in the DEFICIENS/GLOBOSA and AGAMOUS MADS-box subfamilies, which may have resulted from either a proposed genome-wide duplication in the ancestor of extant angiosperms or multiple independent duplication events. Regardless of the mechanism of gene duplication, these pairs of duplicate transcription factors provided new possibilities of genetic interactions that may have been important in the origin of the flower.

PMID:
15687268
[PubMed - indexed for MEDLINE]
PMCID:
PMC1449606
Free PMC Article

Images from this publication.See all images (8)Free text

F igure  1.—
F igure  2.—
F igure  3.—
F igure  4.—
F igure  5.—
F igure  6.—
F igure  7.—
F igure  8.—
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk