Research Paper Volume 1, Issue 2 pp 219—233
WRN helicase defective in the premature aging disorder Werner syndrome genetically interacts with topoisomerase 3 and restores the top3 slow growth phenotype of sgs1 top3
Figure 4. WRN ATPase/helicase, but not exonuclease activity, is required to restore the slow growth phenotype of top3 in sgs1 top3 background. Panel A, WRN protein with conserved domains and positions of site-directed mutations. Panel B, Expression of WRN and WRN variants in transformed sgs1 top3 was induced at 2% gal concentration and cells were harvested after 6 h. Equal amount of total cell lysate was loaded on to 8-16% polyacrylamide SDS gels, followed by Western blotting using anti-WRN antibody. sgs1 top3 strain transformed with ATPase/helicase-dead (YEp195SpGAL-WRN K577M), exonuclease-dead (YEp195SpGAL-WRN E84A), RQC mutant (YEp195SpGAL-WRN K1016A), or polymorphic mutant (YEp195SpGAL-WRN R834C) was streaked on SC-Trp plates containing either 2% glu (Panel E) or 2% gal (Panel D). Plates were incubated at 30°C for 2 days and then photographed. Composition of the plates was as in Panel C.