||A 330bp long HindIII-XbaI fragment from phspCAT (plasmid no. 21, obtained from Alan Wolffʼs lab) containing the hsp
promoter with TATA box was cloned into the pBluescript SK- (Anne Donaldsonʼs prep, plasmid no. 41) to obtain
plasmid pbshsp1 (SH30/6/98). pbshsp1 was then cut w/ XbaI, blunted with Klenow, cut with ScaI and cloned into a
pCS2+ (plasmid no. 1) which had been cut with HindIII, blunted with Klenow and ScaI cut to yield plasmid HS1
(SH9/7/98). Note that blunt ligation recreated functional XbaI site.