Investigation of G72 expression by northern analysis. (A) G72 and β-actin probes were validated using total RNA isolated from mock-transfected HEK-293 cells (M) or cells expressing His-G72 (G72). A strong signal for G72 was only observed in cells expressing His-G72. (B) Using a G72-specific, radioactive probe, no G72 signal was detected on Clontech poly A+ RNA Northern blots. The following brain regions were represented: Human Brain Blot II: 1, putamen. 2, temporal lobe. 3, frontal lobe. 4, occipital pole. 5, spinal cord. 6, medulla. 7, cerebral cortex. 8, cerebellum. Human Brain blot V: 9, thalamus. 10, whole brain. 11, hippocampus. 12, corpus callosum. 13, caudate nucleus. 14, amygdala. (C) Following G72-probing, human brain blots II and V were stripped and reprobed with a β-actin-specific probe in order to ensure RNA integrity and equal loading. Signal strength was similar in all lanes.