Alex Kolodkin is a neuroscientist recognized for his work on understanding the molecular basis underlying neuronal connectivity. He is known for the identification of phylogenetically conserved neuronal guidance cues and their receptors and assessments of their functions in a variety of neural systems. Kolodkin was born in New York City and grew up in western Massachusetts. He graduated from Wesleyan University in Middletown Connecticut with B.A. degrees in Biology and Religious Studies, and from the University of Oregon in Eugene with a Ph.D. in Molecular Biology. Kolodkin was a postdoctoral fellow at the University of California, Berkeley, and then joined the faculty of the Department of Neuroscience at The Johns Hopkins School of Medicine in 1995. He has received the Pradel Award of the National Academy of Sciences, and he is an elected member of the National Academy of Sciences, the National Academy of Medicine, the American Academy of Arts and Sciences, and the American Association for the Advancement of Science.

Research Interests

Alex Kolodkin's laboratory studies how the nervous system is wired up during development, work that is supported by his discovery and analysis of neuronal guidance cues and their receptors. He led in the discovery of one of the largest families of phylogenetically conserved guidance cues, the semaphorins, and with David Ginty identified the first semaphorin receptor, neuropilin-1. Kolodkin provided in vivo evidence in the Grasshopper, Drosophila, and in mice showing how semaphorins and their receptors direct neuronal connectivity in multiple neural systems. Kolodkin's laboratory has exploited genetic and molecular approaches to identify key intracellular signaling components that function in vivo downstream semaphorin receptors, work demonstrating that unique intracellular guidance cue signaling events mediate distinct effects on axon guidance, dendritic process morphology, axon pruning and synapse organization. The Kolodkin laboratory has identified key repulsive guidance cues and receptors that function in vivo to direct laminar stratification in the mouse retina and has shown that these are critical for formation of functional direction-selective circuits. Kolodkin's work provides a framework for understanding how a limited number of guidance molecules is capable of sculpting, maintaining, and refining complex neural circuitry. These discoveries also impact our understanding of signaling events underlying neural regeneration following injury or degeneration, and they inform our understanding of non-neuronal tissue morphogenesis and a variety of disease conditions.

Membership Type


Election Year


Primary Section

Section 24: Cellular and Molecular Neuroscience

Secondary Section

Section 22: Cellular and Developmental Biology