Shortly after the burst

Prof. Mike Greenberg talks about his research on Immediate Early Genes 

Despite similarities in the numbers of genes and structure of neural circuits, primates have evolved vastly more complex brains and behaviors. What do those differences look like in the brain? A recent paper from the labs of Michael Greenberg and Margaret Livingstone at Harvard Medical School examines how a short (85 base pairs!) sequence in the regulatory region of the OSTN gene, which was previously known as a secreted protein in bone and muscle development, has allowed it to be expressed in the brains of primates, but not those of rodents. The expression of OSTN is special for another reason: it is one of the first primate-specific genes regulated by immediate early genes (IEGs) to be found. IEGs are a group of genes whose transcription in neurons is transient and commonly follows a burst of spiking activity. In their short window of expression many IEGs are known to regulate expression of specific downstream genes. The new paper from the Greenberg and Livingstone labs gives us a peak into how small differences in common molecular pathways may be implicated in the diversity of species. The journey of our knowledge and understanding of IEGs and the genetic response to neural activity is also the journey of the scientist who first observed the expression patterns of IEGs, and who has since dedicated a great deal of his scientific career to investigating them: Professor Michael Greenberg. A few weeks ago, I had the pleasure of sitting down with him to talk about his work, past, present and future.

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