tokens: The promoters and enhancers of cell type-specific genes are often conserved in evolution , and hence one might expect that a given enhancer has evolved to work best with its own promoter .
folded_tokens: the promoters and enhancers of cell type-specific genes are often conserved in evolution , and hence one might expect that a given enhancer has evolved to work best with its own promoter .
labels: O B-DNA_family_or_group O B-DNA_family_or_group O O O O O O O O O O O O O O O O O O B-DNA_domain_or_region O O O O O O O O B-DNA_domain_or_region O