Microtubules are not required for glucocorticoid receptor mediated gene induction.
Steroid-free glucocorticoid receptors are generally considered to reside in the cytoplasm of cells. After the binding of steroids, the receptors translocate into the nucleus in a manner that has been proposed to involve microtubules. However, some results with inhibitors of microtubule assembly argue to the contrary. In all of these studies, only the whole cell localization of receptors has been examined; the biological activity of these receptors has not been determined. We now report that steroid-induced gene expression is maintained in the absence of intact microtubules. This argues that microtubules are not required for either the nuclear translocation or biological activity of glucocorticoid receptors.
Szapary
D
D
Steroid Hormones Section, Laboratory of Molecular and Cellular Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892.
Barber
T
T
Dwyer
N K
NK
Blanchette-Mackie
E J
EJ
Simons
S S
SS
D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D003078:Colchicine / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation / Q000187:drug effects; D017930:Genes, Reporter / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D013256:Steroids / Q000494:pharmacology; D015533:Transcriptional Activation; D014162:Transfection
D011965:Receptors, Glucocorticoid; D013256:Steroids; D003078:Colchicine