This gene encodes a member of the claudin family. Claudins are integral membrane proteins and components of tight junction strands. Tight junction strands serve as a physical barrier to prevent solutes and water from passing freely through the paracellular space between epithelial or endothelial cell sheets, and also play critical roles in maintaining cell polarity and signal transductions. This gene is upregulated in patients with ulcerative colitis and highly overexpressed in infiltrating ductal adenocarcinomas. PKC/MAPK/AP-1 (protein kinase C/mitogen-activated protein kinase/activator protein-1) dependent pathway regulates the expression of this gene in gastric cells. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jun 2010]
Transcription factors with Perturb-seq knockdown data for CLDN18. The Binding column indicates whether any binding evidence exists for this TF–gene pair (ChIP-seq or motif footprint peaks). The Mean coef is the average Perturb-seq regression coefficient across active gRNAs (positive = CLDN18 upregulated upon KD; negative = downregulated). The Outlier column indicates whether this gene is in the top or bottom 5% of all TF knockdown effects.
| TF | Mean coef | Binding | Outlier | TF→Gene link |
|---|
Open chromatin peaks (ATAC-seq) in the genomic neighbourhood of CLDN18, linked by TSS proximity or chromatin conformation (Multiome / HiCAR). Each element overlaps at least one TF ChIP-seq binding site — the TFs column shows how many distinct TFs bind that element.
| Accessibility | Element | Dist. to TSS | Link type | TFs |
|---|---|---|---|---|
| chr3:138,009,757–138,010,666 | at TSS | At TSS | 133 | |
| chr3:138,011,772–138,012,215 | 1.6 kb | Proximal (<10kb) | 68 | |
| chr3:138,019,195–138,020,432 | 9.0 kb | Proximal (<10kb) | 203 |
Genomic view of the CLDN18 locus showing ATAC-seq accessibility and RNA-seq expression across the ESC → DE time course, together with TF binding peaks and element-to-TSS loop connections.