Fig 1. The genomic structure of RXFP1 and core promoter activity.

(A) Location of the Long and Short forms of RXFP1 with identification of their mapped transcripts on chromosome 4 is shown. Genomic locations were determined based on the human genome build hg38 (https://genome.ucsc.edu/). The putative proximal and distal promoters are shown. (B) Proximal and distal core (P-Core and D-core, respectively) promoter activity analysis using a Luciferase promoter reporting system is shown. Transfections were performed in quadruplicates using Lipofectamine 2000 (Thermo-Fisher). Both control (CL) and idiopathic pulmonary fibrosis (IPF) lung fibroblasts were used. The promoter activity (fold) was calculated using pGL3basic (pB) as a control. Three control and 3 IPF independent lung fibroblast lines were tested and results from a representative experiment are shown as mean ± standard deviation. P-values for pairwise comparison using student T-test (two tailed) are shown. (C) Chromatin characteristics associated with active transcriptional regulation including H3K4Me1, H3K27Ac, H3K4Me3 and DNAse sensitivity clusters for the P-Core and D-Core region identified using the Encyclopedia of DNA Elements (ENCODE) histone ChIP data (https://genome.ucsc.edu/) are shown. The nucleotide location relative to each of the transcription start sites (TSS) are labelled. RXFP1, Relaxin/insulin-like family peptide receptor 1; UCSC, University of California, Santa Cruz.