Deletion analysis of upstream <i>cis</i>-acting elements of <i>map4</i>⁺.

<p>(A) Putative promoter sequence of the <i>map4</i>^<i>+</i> gene. Two possible TR-box elements (blue and green) and a TATA-like box (red) are italicized and underlined. The transcription start site was identified by sequencing of several cDNA clones (Nakamura <i>et al</i>, unpublished). (B) β-galactosidase assay of the promoter intensity of a <i>map4</i> promoter-<i>lacZ</i> fusion gene with different deletions of the promoter sequence of the <i>map4</i> gene. A heterothallic <i>h</i>⁺ strain (FS85) was transformed with the multicopy plasmid pTA(map4^PRO-lacZ) or the deletion constructs. Cells of the transformants were precultured in SSL+N without leucine and then transferred to SSL−N medium containing 200 nM of synthetic M-factor (filled bar) or SSL−N alone (open bar). After 6 hr, β-gal activity was assayed.