Evolution of Anthocyanin Biosynthesis in Maize Kernels: The Role of Regulatory and Enzymatic Loci
AUTOR(ES)
Hanson, M. A.
RESUMO
Understanding which genes contribute to evolutionary change and the nature of the alterations in them are fundamental challenges in evolution. We analyzed regulatory and enzymatic genes in the maize anthocyanin pathway as related to the evolution of anthocyanin-pigmented kernels in maize from colorless kernels of its progenitor, teosinte. Genetic tests indicate that teosinte possesses functional alleles at all enzymatic loci. At two regulatory loci, most teosintes possess alleles that encode functional proteins, but ones that are not expressed during kernel development and not capable of activating anthocyanin biosynthesis there. We investigated nucleotide polymorphism at one of the regulatory loci, c1. Several observations suggest that c1 has not evolved in a strictly neutral manner, including an exceptionally low level of polymorphism and a biased representation of haplotypes in maize. Curiously, sequence data show that most of our teosinte samples possess a promoter element necessary for the activation of the anthocyanin pathway during kernel development, although genetic tests indicate that teosinte c1 alleles are not active during kernel development. Our analyses suggest that the evolution of the purple kernels resulted from changes in cis regulatory elements at regulatory loci and not changes in either regulatory protein function nor the enzymatic loci.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1207407Documentos Relacionados
- Role of the regulatory gene pl in the photocontrol of maize anthocyanin pigmentation.
- Auxin Biosynthesis in Maize Kernels1
- Molecular analysis of the maize anthocyanin regulatory locus C1.
- Maize anthocyanin regulatory gene pl is a duplicate of c1 that functions in the plant.
- Molecular analysis of the anthocyanin2 gene of petunia and its role in the evolution of flower color.