Bystin is expressed as a 2-kb major transcript and a 3.6-kb minor transcript in SNG-M cells and in human trophoblastic teratocarcinoma HT-H cells. Protein binding assays determined that bystin binds directly to trophinin and tastin, and that binding is enhanced when cytokeratins 8 and 18 are present. Immunocytochemistry of HT-H cells showed that bystin colocalizes with trophinin, tastin, and the cytokeratins, suggesting that these molecules form a complex in trophectoderm cells at the time of implantation. Using immunohistochemistry it was determined that trophinin and bystin are found in the placenta from the sixth week of pregnancy. Both proteins were localized in the cytoplasm of the syncytiotrophoblast in the chorionic villi and in endometrial decidual cells at the uteroplacental interface. After week 10, the levels of trophinin, tastin, and bystin decreased and then disappeared from placental villi. [provided by RefSeq, Jul 2008]
Transcription factors with Perturb-seq knockdown data for BYSL. 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 = BYSL 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 BYSL, 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 |
|---|---|---|---|---|
| chr6:41,638,107–41,639,488 | 283.0 kb | Distal (>10kb) Multiome | 240 | |
| chr6:41,683,281–41,684,037 | 237.7 kb | Distal (>10kb) Multiome | 492 | |
| chr6:41,733,652–41,736,107 | 187.2 kb | Distal (>10kb) Multiome | 908 | |
| chr6:41,779,509–41,781,116 | 141.4 kb | Distal (>10kb) Multiome HiCAR | 857 | |
| chr6:41,786,100–41,787,779 | 135.0 kb | Distal (>10kb) Multiome HiCAR | 1106 | |
| chr6:41,894,347–41,896,221 | 26.1 kb | Distal (>10kb) Multiome | 822 | |
| chr6:41,920,834–41,921,901 | 233 bp | At TSS Multiome | 955 | |
| chr6:41,939,116–41,939,782 | 17.9 kb | Distal (>10kb) Multiome | 401 | |
| chr6:41,940,689–41,942,238 | 20.4 kb | Distal (>10kb) Multiome | 798 | |
| chr6:41,965,433–41,966,075 | 44.3 kb | Distal (>10kb) Multiome | 152 | |
| chr6:42,030,637–42,031,169 | 109.5 kb | Distal (>10kb) Multiome HiCAR | 297 | |
| chr6:42,048,292–42,049,051 | 127.2 kb | Distal (>10kb) Multiome HiCAR | 627 | |
| chr6:42,050,080–42,050,921 | 129.1 kb | Distal (>10kb) Multiome | 912 | |
| chr6:42,104,179–42,104,979 | 182.9 kb | Distal (>10kb) Multiome | 486 | |
| chr6:42,136,520–42,137,140 | 215.3 kb | Distal (>10kb) Multiome | 555 | |
| chr6:42,142,113–42,142,966 | 221.1 kb | Distal (>10kb) Multiome | 489 | |
| chr6:42,166,489–42,167,048 | 245.2 kb | Distal (>10kb) Multiome | 451 | |
| chr6:42,177,902–42,178,547 | 256.7 kb | Distal (>10kb) Multiome | 161 |
Genomic view of the BYSL 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.