Characterization of the bi-directional transcriptional control region between the human UFD1L and CDC45L genes

The human UFD1L and CDC45L genes, adjacently located in the head-to-head di rection on chromosome 22q11, are separated by a 884 base-pair (bp) segment constituting the putative transcriptional control region, In this region we mapped one transcription start site at 69 bp upstream of UFD1L gene, and o ne major and one minor start sites at 76 bp and 503 bp upstream of CDC45L g ene, which are to center in the putative core promoters designated as P-UFD 1L, P-CDC45L/major, and P-CDC45L/minor, respectively. The three core promot ers lacked a TATA-motif and had a high GC-content. To determine the approxi mate ranges for the regulatory promoters, the 884-bp fragment or those with a series of deletions were placed between firefly and renilla luciferase g enes present in the head-to-head direction in a single plasmid, and the res ulting plasmids were assayed for the two transiently induced enzyme activit ies. The P-UFD1L and P-CDC45L/major regulatory promoters were within 418 an d 454 bp upstream of the respective start sites and their greater parts wer e not overlapping. The activity of P-CDC45L/minor regulatory promoter was m arkedly enhanced when P-CDC45L/major and its regulatory promoter were delet ed. The deletion analyses revealed the basal activities of the three core p romoters, which were enhanced by approximately twofold by the respective re gulatory promoters, on the transfected DNA templates. (C) 2001 Academic Pre ss.