title: Genomic deletion of a long-range bone enhancer misregulates sclerostin in Van Buchem disease.
abstract: Mutations in distant regulatory elements can have a negative impact on human development and health, yet because of the difficulty of detecting these critical sequences, we predominantly focus on coding sequences for diagnostic purposes. We have undertaken a comparative sequence-based approach to characterize a large noncoding region deleted in patients affected by Van Buchem (VB) disease, a severe sclerosing bone dysplasia. Using BAC recombination and transgenesis, we characterized the expression of human sclerostin (SOST) from normal (SOST(wt)) or Van Buchem (SOST(vbDelta) alleles. Only the SOST(wt) allele faithfully expressed high levels of human SOST in the adult bone and had an impact on bone metabolism, consistent with the model that the VB noncoding deletion removes a SOST-specific regulatory element. By exploiting cross-species sequence comparisons with in vitro and in vivo enhancer assays, we were able to identify a candidate enhancer element that drives human SOST expression in osteoblast-like cell lines in vitro and in the skeletal anlage of the embryonic day 14.5 (E14.5) mouse embryo, and discovered a novel function for sclerostin during limb development. Our approach represents a framework for characterizing distant regulatory elements associated with abnormal human phenotypes.
authors.affiliation: Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. loots1@llnl.gov
authors.forename: Gabriela G
authors.initials: GG
authors.lastname: Loots
authors.forename: Michaela
authors.initials: M
authors.lastname: Kneissel
authors.forename: Hansjoerg
authors.initials: H
authors.lastname: Keller
authors.forename: Myma
authors.initials: M
authors.lastname: Baptist
authors.forename: Jessie
authors.initials: J
authors.lastname: Chang
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Collette
authors.forename: Dmitriy
authors.initials: D
authors.lastname: Ovcharenko
authors.forename: Ingrid
authors.initials: I
authors.lastname: Plajzer-Frick
authors.forename: Edward M
authors.initials: EM
authors.lastname: Rubin
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015519:Bone Density / Q000235:genetics; D019485:Bone Morphogenetic Proteins / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D008040:Genetic Linkage; D005819:Genetic Markers / Q000235:genetics*; D006801:Humans; D015576:Hyperostosis / Q000235:genetics*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D010641:Phenotype; D051381:Rats; D016415:Sequence Alignment; D014407:Tumor Cells, Cultured; D020506:Untranslated Regions
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; D005819:Genetic Markers; C422903:SOST protein, human; D020506:Untranslated Regions