Spatiotemporal dog brain proteome

The complexity and low accessibility of the human brain make it challenging to understand its development, function, and disorders. Brain diseases including neurodegenerative disease and psychiatric diseases incur huge medical and social burdens without effective treatments. While mouse has substantially contributed to our current understanding of brain, the translational value of mouse models may limit to certain aspects of a disease due to the apparent differences in brain structure (gyrencephalic versus lissencephalic) and behavior between mice and humans. Nonhuman primates are, in theory, the best animals to understand human brains. However, monkeys are extremely expensive and inefficient to reproduce (5 years to reach sexual maturity and only one progeny per pregnancy). Dogs have similar gyrencephalic brain structure as humans. Due to the human selection and domestication, dogs have developed exquisite and complex dog-human heterospecific social capabilities. For example, dogs can learn by observing human social and communicative behaviors such as a pointing gesture to find hidden food. Indeed, psychologists have learned that average dogs can count, reason and recognize words and gestures on par with a human 2-year-old. Compared with nonhuman primates, dogs have relatively lower costs of husbandry and shorter breeding times, with multiple offspring per pregnancy. Given that gene editing and animal cloning by somatic nuclear transfer have been available in dogs in recent years and other advantages described above, dogs are thus a potential model for studying human brain development and disease. However, to what extent the dog brain is conserved with the human brain at the molecular level remains unclear.