SACCHAROMYCES-CEREVISIAE BUF PROTEIN BINDS TO SEQUENCES PARTICIPATINGIN DNA-REPLICATION IN ADDITION TO THOSE MEDIATING TRANSCRIPTIONAL REPRESSION (URS1) AND ACTIVATION
Rm. Luche et al., SACCHAROMYCES-CEREVISIAE BUF PROTEIN BINDS TO SEQUENCES PARTICIPATINGIN DNA-REPLICATION IN ADDITION TO THOSE MEDIATING TRANSCRIPTIONAL REPRESSION (URS1) AND ACTIVATION, Molecular and cellular biology, 13(9), 1993, pp. 5749-5761
The heteromeric BUF protein was originally shown to bind to URS1 eleme
nts which are situated upstream of many genes in Saccharomyces cerevis
iae and mediate negative control of their transcription. Among the gen
es regulated through the URS1 site and the proteins interacting with i
t are those participating in carbon, nitrogen, and inositol metabolism
; electron transport; meiosis; sporulation; and mating-type switching.
We show here that pure BUF protein, in addition to binding to the neg
atively acting URS1 site, also binds to CAR1 sequences supporting tran
scriptional activation (upstream activation sequences). To determine t
he BUF protein structure, we cloned and sequenced the BM and BUF2 gene
s and found them to be identical to the RF-A (RP-A) genes whose produc
ts participate in yeast DNA replication as single-stranded DNA binding
proteins. These data argue that BUF protein-binding sites serve multi
ple roles in transcription and replication.