HMG-proteins 1 and 2 are required for transcription of chromatin by endogenous RNA polymerase

An androgen receptor was isolated and partially purified from the cytosol fraction of ram seminal vesicles. An almost two thousand fold purification with a recovery of 33% could be obtained by chromatography on 2′,5′-ADP-sepharose, ammoniumsulphate precipitation and gel filtration on Ultrogel ACA-44. The labelled receptor was characterized by electrophoresis and sucrose gradient centrifugation (sedimentation at approximately 3S). The purified receptor has a DNA binding-site and is specific for androgenic steroids.     

Evidence for specific control of RNA polymerase synthesis in Escherichia coli

Studies on the synthesis of RNA polymerase in E. coli rif mutants containing both sensitive and resistant RNA polymerase molecules show that the synthesis of E. coli RNA polymerase is under a specific and active control system.