The Journal of Neuroscience, June 24, 2009, 29(25):8288-8297; doi:10.1523/JNEUROSCI.0097-09.2009
Previous Article
Cellular/Molecular
Histone Deacetylases 1 and 2 Form a Developmental Switch That Controls Excitatory Synapse Maturation and Function
Mohd W. Akhtar,1
Jesica Raingo,2
Erika D. Nelson,1
Rusty L. Montgomery,3
Eric N. Olson,3
Ege T. Kavalali,2,4 and
Lisa M. Monteggia1
Departments of 1Psychiatry, 2Neuroscience, 3Molecular Biology, and 4Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9111
Correspondence should be addressed to either of the following: Lisa M. Monteggia, Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9070, Email: lisa.monteggia{at}utsouthwestern.edu; or Ege T. Kavalali, Department of Neuroscience, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9111, E-mail: Email: ege.kavalali{at}utsouthwestern.edu
The structural assembly of synapses can be accomplished in a rapid time frame, although most nascent synapses formed during early development are not fully functional and respond poorly to presynaptic action potentials. The mechanisms that are responsible for this delay in synapse maturation are unknown. Histone deacetylases (HDACs) regulate the activity state of chromatin and repress gene expression through the removal of acetyl groups from histones. Class I HDACs, which include HDAC1 and HDAC2, are expressed in the CNS, although their specific role in neuronal function has not been studied. To delineate the contribution of HDAC1 and HDAC2 in the brain, we have used pharmacological inhibitors of HDACs and mice with conditional alleles to HDAC1 and HDAC2. We found that a decrease in the activities of both HDAC1 and HDAC2 during early synaptic development causes a robust facilitation of excitatory synapse maturation and a modest increase in synapse numbers. In contrast, in mature neurons a decrease in HDAC2 levels alone was sufficient to attenuate basal excitatory neurotransmission without a significant change in the numbers of detectable nerve terminals. Therefore, we propose that HDAC1 and HDAC2 form a developmental switch that controls synapse maturation and function acting in a manner dependent on the maturational states of neuronal networks.
Received Jan. 8, 2009;
revised April 21, 2009;
accepted May 26, 2009.
Correspondence should be addressed to either of the following: Lisa M. Monteggia, Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9070, Email: lisa.monteggia{at}utsouthwestern.edu; or Ege T. Kavalali, Department of Neuroscience, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9111, E-mail: Email: ege.kavalali{at}utsouthwestern.edu