Complex sentence: Binding of hormone to the GR causes transient dissociation of heat shock protein, translocation into the nucleus, dimerization, and binding to specific sequences of DNA, which facilitate upregulation of GR responsive genes.
Split into simpler sentences: Binding of hormone to the GR causes transient dissociation of heat shock protein. Once in the nucleus, GR dimerizes and binds to specific sequences of DNA which facilitate upregulation of GR responsive genes.