title: Shadow enhancers: frequently asked questions about distributed cis-regulatory information and enhancer redundancy.
abstract: This paper, in the form of a frequently asked questions page (FAQ), addresses outstanding questions about "shadow enhancers", quasi-redundant cis-regulatory elements, and their proposed roles in transcriptional control. Questions include: What exactly are shadow enhancers? How many genes have shadow/redundant/distributed enhancers? How redundant are these elements? What is the function of distributed enhancers? How modular are enhancers? Is it useful to study a single enhancer in isolation? In addition, a revised definition of "shadow enhancers" is proposed, and possible mechanisms of shadow enhancer function and evolution are discussed.
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA. sbarolo@umich.edu
authors.forename: Scott
authors.initials: S
authors.lastname: Barolo
mesh_terms: D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D023281:Genomics; D006801:Humans; D014158:Transcription, Genetic
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