HUMAN R1 SUBUNIT OF RIBONUCLEOTIDE REDUCTASE (RRM1) - 5' FLANKING REGION OF THE GENE

Ribonucleotide reductase is essential, in dividing cells, for the prod uction of deoxyribonucleotides prior to DNA synthesis in S phase. Neit her of its two subunits (R1 and R2) are detectable in quiescent cells. In cycling cells, RRM1 mRNA and R1 protein are present throughout the cell cycle. A fragment of the human cDNA was used to isolate a genomi c clone that encompasses the 5' flanking region of human RRM1. Primer extension and PCR experiments were used to define six potential cap si tes. The immediate upstream region does not have a TATA box and is not GC-rich. A 1.9-kb fragment (-1670 to +208) was able to direct transcr iption of a reporter gene in a transient expression system. Understand ing the mechanisms regulating expression of this gene will provide ins ight into the processes involved in cell cycling and may be of particu lar importance in understanding the deregulated growth of transformed cells. (C) 1994 Academic Press, Inc.