Tissue-specific modulation of rat glucocorticoid receptor binding activity by melatonin

The effect of melatonin and 2-Iodomelatonin on nuclear and cytosolic glucocorticoid receptors in the brain, pituitary, thymus and liver has been examined. The results indicate that both melatonin and 2-Iodomelatonin administration is associated with marked changes in the density and the affinity of cytosolic and nuclear forms of glucocorticoid receptors. These observations are discussed in the context of a possible involvement of pineal melatonin in the mechanisms regulating the behaviour and metabolism of steroid receptors.     

Diversity of microRNAs in human and chimpanzee brain

We used massively parallel sequencing to compare the microRNA (miRNA) content of human and chimpanzee brains, and we identified 447 new miRNA genes. Many of the new miRNAs are not conserved beyond primates, indicating their recent origin, and some miRNAs seem species specific, whereas others are expanded in one species through duplication events. These data suggest that evolution of miRNAs is an ongoing process and that along with ancient, highly conserved miRNAs, there are a number of emerging miRNAs.