Construct 48.1C contains the complete
hsp16-48/1 gene pair of locus
hsp16A (Russnak and Candido, 1985) and is an in-frame translational fusion of the lacZ coding region with the second exon of
hsp16-1. The presence of an SV40 nuclear localization signal in the fusion targets lacZ expression to the nucleus, facilitating cell identification (Fire et al., 1990). pPCZ1 or 48.1C was constructed by inserting a 3500bp HindIII-AflI fragment encompassing the lacZ gene (nucleotides 18-3518 of the expression vector pPD16.43 received from A.Fire, Carnegie Institution) into the HpaI site (nucleotide 3565 of the published sequence) of the hspl6-1 gene. pPCZ1 contains a complete hspl6-48/1 gene pair extending from a BclI site at nucleotide 2280 to the BamHI site at nucleotide 4186 in the published sequence (Russnak and Candido,1985).