The Impact of Local Genome Sequence on Defining Heterochromatin Domains

摘要: Characterizing how genomic sequence interacts with trans-acting regulatory factors to implement a program of gene expression in eukaryotic organisms is critical understanding genome function. One means by which patterns are achieved through the differential packaging DNA into distinct types chromatin. While chromatin state exerts major influence on expression, extent cis-acting sequences contribute specification remains incompletely understood. To address this, we have used fission yeast element (L5), known be sufficient nucleate heterochromatin, establish de novo heterochromatin domains Schizosaccharomyces pombe genome. The resulting were queried for presence H3K9 di-methylation and Swi6p, both hallmarks levels expression. We describe effect determining size such domains. Heterochromatin spreading antagonized genes, manner that can occur independent strength transcription. Increasing dosage Swi6p results increased proximal L5 element, but does not result an expansion domain, suggesting this context effects dominant over trans effects. Finally, show ratio sequence-dependent correlates repression. Taken together, these data demonstrate content region plays significant role shaping its response encroaching suggest specifying state.