Transcription of genes encoding pregnancy-specific glycoproteins is regulated by negative promoter-selective elements

PANZETTA-DUTARI G.; KORITSCHONER N.; BOCCO J.L.; NORES R.; DUMUR C.; PATRITO L.

PORTLAND PRESS LTD

Lugar: Londres; Año: 2000 vol. 350 p. 511 - 511

he human pregnancy-specific glycoprotein (PSG) genes comprise a family of 11 highly conserved members whose expression is maximal in placental cells and marginal in other cell types. We have investigated here the molecular basis of PSG regulation by analysing a large regulatory region of the PSG-5 gene in cells that do and do not express these genes. The promoter region (-254 to -43), which does not contain a TATA-box, large GC-rich sequences or a classical initiator, was active in all cell types analysed. Additional upstream sequences up to position -3204 repressed promoter activity. Two independent repressor regions were identified and found to operate effectively in HeLa, COS-7 and HTR8/SVneo placental cells. More significantly, these negatively acting modules failed to repress a heterologous TATA-containing thymidine kinase promoter. Detailed transcriptional and DNA-protein analyses of the proximal repressor region (-605 to -254) revealed the presence of both negative and positive