Nuclear localization of a steroid receptor. (A) The mineralocorticoid receptor, made visible by attachment to a yellow variant of GFP, is located predominantly in the cytoplasm of the cultured cell. (B) Subsequent to the addition of corticosterone (a glucocorticoid steroid that also binds to the mineralocorticoid receptor), the receptor moves into the nucleus.
[M. Nishi, M. Tanaka, K.-i. Matsuda, M. Sunaguchi, and M. Kawata. J. Neurosci. 24:4918–