O-Sialoglycoprotein Endopeptidase Like Protein 1 (OSGEPL1)

OSGEPL1 belongs to the peptidase M22 family. The OSGEP gene is 7.75 kb long, consists of 11 exons and 10 introns, and lies immediately adjacent to the APEX gene (which encodes APEX nuclease, a multifunctional DNA repair enzyme) in 5'-to-5' orientation.

The promoter region of the OSGEP gene lacks the typical TATA box, but has putative regulatory elements in the CpG island. Northern blot analysis showed ubiquitous expression of the OSGEP gene in several tissues, and observed similarities in expression patterns between OSGEP and APEX. A functional region required for full transcription activity was narrowed down to a 23 bp region containing a CCAAT box. It has been reported that this CCAAT box promotes basal transcription in the APEX direction.