Three-Toed Sloth

SUMO versus the Dendritic Claws (Sunday Sibling Blogging)

I occasionally dabble in mathematical aspects of neuroscience. My brother does the real thing:

Aryaman Shalizi, Brice Gaudillière, Zengqiang Yuan, Judith Stegmüller, Takahiro Shirogane, Qingyuan Ge, Yi Tan, Brenda Schulman, J. Wade Harper,and Azad Bonni, "A Calcium-Regulated MEF2 Sumoylation Switch Controls Postsynaptic Differentiation", Science 311 (2006): 1012--1017

Abstract: Postsynaptic differentiation of dendrites is an essential step in synapse formation. We report here a requirement for the transcription factor myocyte enhancer factor 2A (MEF2A) in the morphogenesis of postsynaptic granule neuron dendritic claws in the cerebellar cortex. A transcriptional repressor form of MEF2A that is sumoylated at lysine-403 promoted dendritic claw differentiation. Activity-dependent calcium signaling induced a calcineurin-mediated dephosphorylation of MEF2A at serine-408 and, thereby, promoted a switch from sumoylation to acetylation at lysine-403, which led to inhibition of dendritic claw differentiation. Our findings define a mechanism underlying postsynaptic differentiation that may modulate activity-dependent synapse development and plasticity in the brain.

Also check out the accompanying "perspectives" piece.

Minds, Brains, and Neurons; Incestuous Amplification