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mouse brain

The human brain contains about 100 billion neurons, each making thousands of synaptic connections. While individual neurons can themselves perform sophisticated information processing, it is the assembly of neurons into circuits via specific patterns of synaptic connections that endows our brain with the computational capacity to sense, act, think, and remember.

How are neurons organized into specialized circuits to perform specific functions? How are these circuits assembled during development? We are investigating these questions in the brains of the fruit fly (~100 thousand neurons) and mouse (~100 million neurons). We have developed molecular-genetic and viral tools, and are combining them with transcriptomic, proteomic, physiological, and behavioral approaches to study these problems.

Current Areas of Research

Selected reviews:


Luo L (2020) Principles of Neurobiology, 2nd edition. 1st edition 2015, 2nd edition 2020; Garland Science/CRC Press

Luo L (2021) Architecture of Neuronal Circuits. Science 373: eabg7285

Neural circuit assembly

Luo L (2000) Rho GTPases in neuronal morphogenesis. Nat Rev Neurosci 1: 173-180.

Luo L (2002) Actin cytoskeleton regulation in neuronal morphogenesis and structural plasticity. Ann Rev Cell Dev Biol 18: 601-635

Luo L & O’Leary DDM (2005) Axon retraction and degeneration in development and disease. Ann Rev Neurosci 28: 127-156.

Luo L & Flanagan JG (2007) Development of continuous and discrete neural maps. Neuron 56: 284-300.

Hong W & Luo L (2014) Genetic control of wiring specificity in the fly olfactory system. Genetics 196:17-29.

Li H, Shuster SA, Li J & Luo L (2018) Linking neuronal lineage and wiring specificity. Neural Dev 13:5.

Neural circuit organization and function

Luo L, Callaway EC & Svoboda K (2008) Genetic dissection of neural circuits. Neuron 57: 634-660.

Schwarz LA & Luo L (2015) Organization of the locus coeruleus-norepinephrine system. Curr Biol 25:R1051-1056.

Callaway EM & Luo L (2015) Monosynaptic circuit tracing with glycoprotein-deleted rabies viruses. J Neurosci 35:8979-8985.

DeNardo LA & Luo L (2017) Genetic strategies to access activated neurons. Curr Opin Neurobiol 45:121-129.

Luo L, Callaway EM & Svoboda K (2018) Genetic dissection of neural circuits: a decade of progress. Neuron 98:256-281.

Wagner MJ & Luo L (2020) Cortex-cerebellum circuits for cognitive processing. Trends Neurosci 43:42-54.