1Department of Anatomy & Neurobiology, Washington University School of Medicine, 2Department of Anthropology, Washington University in St. Louis, 3Mass Spectrometry Research Center, Vanderbilt University Medical Center, 4Department of Biochemistry, Vanderbilt University Medical Center, 5Alamogordo Primate Facility, Holloman Air Force base, 6Department of Biology, University of Massachusetts Amherst, 7Institute for Genome Sciences & Policy, Duke University, 8Department of Biology, Duke University, 9Department of Evolutionary Anthropology, Duke University, 10Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 11Department of Anthropology, The George Washington University
March 26, 2015 9:15, Grand Ballroom D
Although the adult human brain requires 20% of the body’s resting glucose metabolism, no other primate allocates more than 10% of their energy to their brain. However, it is unknown if humans appropriate energy differently across the many neuronal types that compose the neocortex and other brain areas. We performed high-throughput mass spectrometry at high spatial resolution from individual regions (anterior cingulate and primary motor, sensory, and visual cortices) and layers of the neocortex (layers III, IV, and V) and cerebellum (granule cell layer), as well as the caudate nucleus in humans and chimpanzees. A total of 39 proteins were quantified in both species, including 14 that support aerobic metabolism. We explored how the pattern of protein expression varies across regions and cortical layers to provide insights into the energy use of these neural structures between species. Overall, the expression of proteins differed principally in a region- and layer-specific pattern, with subtle differences between species. While human and chimpanzee brains were generally similar in their distribution of proteins related to regulatory functions, they differed more markedly in their expression of proteins supporting aerobic metabolism. In both species, layer III of the neocortex expressed particularly high levels of proteins supporting aerobic metabolism compared to other cortical layers, suggesting that the connectivity within the cerebral hemisphere may be enhanced in both species. This work extends current understanding of energy allocation in the brain that may underlie human cognitive specializations by providing a novel perspective of the molecular phenotype.
This work was supported by the National Science Foundation (DGE-0801634, BCS-0827531, BCS-0827546), the James S. McDonnell Foundation (22002078, 220020293), and the Wenner-Gren Foundation for Anthropological Research.