ChIP-chip analysis to determine GLI2 binding sites. Homo sapiens

Chromatin immunoprecipitation with anti-GLI2 antibody was conducted in human pulomonary microvascular endothelial cells (HPMECs) to determine GLI2 binding sites upstream of FOXF1. An unanticipated and tremendous amount of the non-coding sequences of the human genome are transcribed. Long non-coding RNAs (lncRNAs) are non-protein coding transcripts longer than 200 nucleotides and their functions remain enigmatic. We demonstrate that deletions of lncRNA genes cause a lethal lung developmental disorder, Alveolar Capillary Dysplasia with Misalignment of Pulmonary Veins (ACD/MPV), with parent of origin effects. We identify non-coding overlapping deletions 250 kb upstream to FOXF1 in nine patients with ACD/MPV that arose de novo specifically on the maternally inherited chromosome and delete a fetal lung-specific EST, part of an lncRNA. These deletions define distant cis-regulatory region that harbors a differentially methylated CpG island, binds GLI2 depending on the methylation status of this CpG island, and physically interacts with and up-regulates the FOXF1 promoter, consistent with the absence of the fetal lung-transcribed lncRNA perturbing FOXF1 regulation. LncRNA-mediated chromatin interactions may be responsible for position effect phenomenon and potentially cause many disorders of human development. Overall design: ChIP-chip HPMECs transfected to overxpress GLI2; 2 biological replicates