Molecular Plant Advance Access published online on May 14, 2009
Molecular Plant, doi:10.1093/mp/ssp028
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Epigenetic Programming: The Challenge to Species Hybridization
Plant Reproductive Genetics, GCOE Research Group, Graduate School of Biological Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
1 To whom correspondence should be addressed. E-mail t-kinosita{at}bs.naist.jp, fax and tel. +81-0743-72-6210.
In many organisms, the genomes of individual species are isolated by a range of reproductive barriers that act before or after fertilization. Successful mating between species results in the presence of different genomes within a cell (hybridization), which can lead to incompatibility in cellular events due to adverse genetic interactions. In addition to such genetic interactions, recent studies have shown that the epigenetic control of the genome, silencing of transposons, control of non-additive gene expression and genomic imprinting might also contribute to reproductive barriers in plant and animal species. These genetic and epigenetic mechanisms play a significant role in the prevention of gene flow between species. In this review, we focus on aspects of epigenetic control related to hybrid incompatibility during species hybridization, and also consider key mechanism(s) in the interaction between different genomes.
Key Words: Endosperm epigenetics genomic imprinting species hybridization transposon