title: Buffering and the evolution of chromosome-wide gene regulation.
abstract: Copy number variation (CNV) in terms of aneuploidies of both entire chromosomes and chromosomal segments is an important evolutionary driving force, but it is inevitably accompanied by potentially problematic variations in gene doses and genomic instability. Thus, a delicate balance must be maintained between mechanisms that compensate for variations in gene doses (and thus allow such genomic variability) and selection against destabilizing CNVs. In Drosophila, three known compensatory mechanisms have evolved: a general segmental aneuploidy-buffering system and two chromosome-specific systems. The two chromosome-specific systems are the male-specific lethal complex, which is important for dosage compensation of the male X chromosome, and Painting of fourth, which stimulates expression of the fourth chromosome. In this review, we discuss the origin and function of buffering and compensation using Drosophila as a model.
authors.affiliation: Department of Molecular Biology, Umeå University, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Stenberg
authors.forename: Jan
authors.initials: J
authors.lastname: Larsson
mesh_terms: D000782:Aneuploidy; D000818:Animals; D002875:Chromosomes / Q000235:genetics*; D056915:DNA Copy Number Variations; D004303:Dosage Compensation, Genetic; D004330:Drosophila / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D018628:Gene Dosage; D005786:Gene Expression Regulation; D005804:Genes, Lethal / Q000235:genetics; D042822:Genomic Instability; D006801:Humans; D008297:Male; D010802:Phylogeny; D012641:Selection, Genetic; D014158:Transcription, Genetic