Altered gene expression in plants due to trans interactions between homologous genes.

We have attempted to explain co-suppression in terms of a hypothesis whereby homologous sequences are able to interact somatically in trans, in a manner influenced by sequence context or location. We have speculated that there might be mechanistic similarities between co-suppression and some other trans interaction and epigenetic phenomena in plants, fungi and animals; and that it might be the sequence context in which a gene lies, or its location in the genome that influences the likelihood that it will participate in these phenomena. We suspect that elucidation of the mechanisms behind these phenomena will play a role in developing a better understanding of the relationship between nuclear architecture and gene expression. This, in turn, will be helpful in understanding the developmental regulatory mechanisms that exert control over somatic trans interactions in plants, and perhaps in understanding some aspects of the basis of cellular differentiation in development.