Changes in the proportions of histone H1° subtypes in brain cortical neurons

Histone H1° is found in tissues with little or no cellular proliferation and has been shown to accumulate during cellular terminal differentiation. Two subtypes of H1°, H1°a and H1°b, are present in any tissue where the protein has been detected. We report here the first evidence of an age-dependent change in the proportions of H1° subtypes. In rat cerebral cortex neurons the proportion of H1°a rises from 44% of total H1° at birth to about 80% at day 300. These results show that terminally differentiated neurons synthesize and exchange H1° at a significant rate. © 1987.