Functional analysis of the regulatory region of the yeast phosphatidylserine synthase gene, PSS

The upstream region of the PSS gene contains three positive cis-acting elements, upstream activation sequences 1 and 2 (UAS1 and UAS2) and a TATA box. The 5' end of UAS1 occurs between positions -239 and -209, and that of UAS2 is between positions -172 and -164. UAS2 contains 5'-TTCACATG-3' as a core sequence at positions -161 to -154. Mutational analysis revealed that this octamer is responsible for the control of PSS expression by inositol and choline. The TATA box is located at positions -112 to -108. In addition, PSS contains a negative cis-acting sequence between UAS2 and the TATA box.