Evolutionary pattern in the antR-cor gene in the dwarf dogwood complex (Cornus, Cornaceae)

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
David L. Remington, Associate Professor (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: The evolutionary pattern of the myc-like anthocyanin regulatory gene antR-Cor was examined in the dwarf dogwood species complex (Cornus Subgenus Arctocrania) that contains two diploid species (C. canadensis and C. suecica), their putative hybrids with intermediate phenotypes, and a tetraploid derivative (C. unalaschkensis). Full-length sequences of this gene (~4 kb) were sequenced and characterized for 47 dwarf dogwood samples representing all taxa categories from 43 sites in the Pacific Northwest. Analysis of nucleotide diversity indicated departures from neutral evolution, due most likely to local population structure. Neighbor-joining and haplotype network analyses show that sequences from the tetraploid and diploid intermediates are much more strongly diverged from C. suecica than from C. canadensis, and that the intermediate phenotypes may represent an ancestral group to C. canadensis rather than interspecific hybrids. Seven amino acid mutations that are potentially linked to myc-like anthocyanin regulatory gene function correlate with petal colors differences that characterize the divergence between two diploid species and the tetraploid species in this complex. The evidence provides a working hypothesis for testing the role of the gene in speciation and its link to the petal coloration. Sequencing and analysis of additional nuclear genes will be necessary to resolve questions about the evolution of the dwarf dogwood complex.

Additional Information

Publication
Genetica 130:19-37
Language: English
Date: 2007
Keywords
Cornus, Gene evolution, Hybridization, Myc-like anthocyanin regulatory gene, Nucleotide polymorphism, Polyploid, Speciation

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