Expression analysis of obg, the gene controlling morphological development of Streptomyces griseus IFO 13189

Abstract

The expression of the obg gene of S.griseus, which codes for a GTP-binding protein and controls morphological development of this organism, was studied by Western and Northern blot analyses. Western analysis revealed that Obg protein level sharply decreases just after the onset of aerial mycelium development or at the end of vegetative growth on agar plate cultures, indicating that expression of obg is regulated in a growth phase-dependent manner. The obg gene was found to be transcribed as a mRNA of 1.7 kb and its transcription was cut off just prior to the decrease of Obg protein, indicating that obg gene expression is controlled at the transcription level.