Expression of a yeast gene can be blocked by insertion of short yeast DNA fragments between a UAS and the TATA box

摘要

We have constructed a plasmid, pOV10, which facilitates the introduction of putative upstream activating sequences (UAS) or upstream repressing sequences (URS) from yeast genes into plasmids containing CYC1-lacZ fusions, We have observed that the insertion of yeast se quences from 155 to 195 bp between the UAS and the TATA box of a CYC1-lacZ fusion gene can block P-galactosidase expression. It is suggested that this block is related to the formation of nucleosomes on the DNA.