radicicol

Geldanamycin and radicicol promote activation of SSA3-lacZ.

PLoS Biology: New Articles Daniel W. Neef et al. 2010

To test this hypothesis, the efficacy of the potent Hsp90 inhibitors geldanamycin and radicicol, in promoting human HSF1-dependent yeast growth was evaluated.

PLoS Biology: New Articles Daniel W. Neef et al. 2010

Yeast strain DNY227, harboring the yHSF1-dependent SSA3-lacZ reporter gene, was exposed to DMSO, 10 µM geldanamycin (GD), or 10 µM radicicol for 3 h upon which time reporter gene activation was assessed by β-galactosidase activity assays.

PLoS Biology: New Articles Daniel W. Neef et al. 2010

Exposure to either 10 µM geldanamycin or 10 µM radicicol for 3 h activated expression of the yeast HSF-dependent

PLoS Biology: New Articles Daniel W. Neef et al. 2010

The inability of well-established inhibitors of both mammalian and yeast Hsp90, geldanamycin and radicicol, to promote HSF1-dependent yeast growth suggests that HSF1A is promoting HSF1 activation in yeast independent of Hsp90 inhibition.

PLoS Biology: New Articles Daniel W. Neef et al. 2010

Given that geldanamycin and radicicol cannot promote human HSF1-dependent yeast growth and that HSF1A does not interact with Hsp90, together these data strongly suggest that HSF1A is not acting as an Hsp90 inhibitor in activating HSF1 in yeast or mammalian cells.

PLoS Biology: New Articles Daniel W. Neef et al. 2010

(A) Yeast cells were treated with either 10 µM HSF1A, 10 µM geldanamycin, or 10 µM radicicol and growth was assessed as in

PLoS Biology: New Articles Daniel W. Neef et al. 2010

However, neither geldanamycin nor radicicol were able to promote human HSF1-dependent yeast growth under the same conditions in which they are potent Hsp90 inhibitors (

PLoS Biology: New Articles Daniel W. Neef et al. 2010