Michael V. L. Bennett (1931 to 2023): A world-renowned authority in the field of electrical synapses in the nervous system

Michael V. L. Bennett, widely known as Mike, passed away on November 16, 2023, in New York City. Late at night, being at home, he felt bad and was brought to the ER, where 4 hours later he passed away. His unexpected death came at a time when he was Distinguished Emeritus in the Dominick P. Purpura Department of Neuroscience at Albert Einstein College of Medicine in New York. This sad event ended the career of a remarkable neuroscientist whose profound contributions have left an enduring legacy that deeply impacted the field of neuroscience. He will be greatly missed by his family, friends, and colleagues. His scientific legacy and mentorship will continue to inspire future generations through his numerous trainees and collaborators around the globe.

Mike Bennett embracing the bust of Golgi at the Rose F. Kennedy Neuroscience Building at Albert Einstein College of Medicine in New York. Image credit: Albert Einstein College of Medicine.

Mike Bennett’s great scientific career started at Yale University where he obtained his undergraduate degree in Zoology. Then, being awarded a Rhodes Scholarship at Oxford University, he obtained his D.Phil. from Balliol College in 1957. In 1960, he was promoted from Assistant to Associate Professor in Neurology at Columbia University. Then, he was recruited to the Albert Einstein College of Medicine as a professor of anatomy in the Department of Neuroscience. He became the Sylvia and Robert S. Olnick Professor of Neuroscience in 1986 and served as chair of the Department of Neuroscience from 1982 to 1996. Mike was named a Distinguished Emeritus Professor in 2005. His department was regarded as a world reference center for research on diverse aspects of gap junctions. Mike’s remarkable contributions to the understanding of electrotonic coupling mediated by gap junctions (electrical synapses) for neural synchrony in the nervous system resulted in his election as a member of the National Academy of Sciences in 1981. His work shed light on the regulation of gap junctions by voltage, intracellular pH, protein phosphorylation, and intracellular Mg²⁺ concentration, among others. His most recent research included studies of unpaired gap junction hemichannels (half gap junction channels present in non-appositional cell membranes) and their role in pathologies of the central nervous system.

Despite his initial reluctance to accept the existence of functional hemichannels in mammalian cells, Mike guided and supported the elegant demonstration of their occurrence. A relevant issue was the discovery that the conductance of a hemichannel was twice that of its corresponding gap junction channel. This groundbreaking demonstration inspired numerous researchers to work on hemichannels. As a result, Mike and many scientists from diverse fields actively contributed to demonstrate roles of hemichannels in stroke, Alzheimer’s disease, growth factor signaling, redox sensitivity, HIV infection, and neuroinflammation, among other fields. The existence of hemichannels also offered an explanation for the diverse physiological responses in peripheral tissues and the central nervous system.

Mike in one of his visits to Uruguay, South America (Casapueblo—Punta del Este—Maldonado—2011), with Verónica Abudara, one of his collaborators on hemichannels in the spinal cord. Image credit: Verónica Abudara (Universidad de la República, Montevideo, Uruguay).

Mike strongly believed in microscopical observations and results derived from objective quantifications. Possibly following from this preference, he was a visionary 40 years ago in enthusiastically supporting the early work on Caenorhabditis elegans performed by David Hall who is now a renowned scientist of this highly recognized biological model, including connectomics and the roles of gap junctions there.

Besides his strong contribution to the understanding of electrical synapses, he also made significant contributions in the field of chemical synapses. In close collaboration with his beloved wife, Dr. R. Suzanne Zukin, Mike generated significant advances to further understand the biophysical properties, protein kinase regulatory mechanisms, and functional relevance of three glutamate receptors (mGluR1, AMPA, and NMDA receptors). Their findings provided a key mechanism whereby neuromodulatory systems targeting these kinases can regulate synaptic function and fine-tune neuronal circuits. The duo also contributed relevant information to support the so-called “GluR2 hypothesis,” establishing that calcium ion-permeable AMPA receptors that lack the GluR2 subunit contribute significantly to the delayed degeneration that follows global ischemia and experimental epilepsy.

Besides being an exceptional scientist, Mike was strongly committed to training young scientists. As a member of the Marine Biological Laboratories (MBL) Society (Woods Hole, MA) and together with John Dowling, Mike created the Neurobiology course at the MBL, which is considered as a neuroscience course of excellence. The door to Mike’s office was always open. He was a consistent figure at all scientific meetings and friendship gatherings, such as departmental retreats and Friday happy hours. There, he shared a beer and conversed with colleagues and students about broad subjects of general interest, including politics, art, and science. Discussions with him were always enriching. Mike constantly attended departmental seminars where his opinion was always highly valued. He could summarize the main findings in a few words and his insightful inquiries prompted profound understanding and reflection among all attendees. He was very generous with a large community of scientists, creating a formidable international network. He was a mentor and friend and left an indelible mark on all of them.

At the Lincoln Center in New York, Mike (Left) and Suzanne (second from Right) after the graduation of Geoffrey Lau (Right). Geoffry worked on glutamate receptors during his Ph.D. at the Albert Einstein College of Medicine. [Rebecca Chin (second from Left), Geoff’s wife, and Geoff are both faculty at City University of Hong Kong]. Image credit: Chun-Yue Geoffrey Lau (City University of Hong Kong, Hong Kong, China).

One of Mike’s notable traits was his profound affinity for animals, mirrored in his choice of office companions, typically reptiles and dogs. It was a familiar sight to see one of his sizable dogs accompanying him to the office after their morning runs independently of the season.

On behalf of my colleagues and myself, in this brief retrospective, I would like to express our gratitude for his friendship and intellectual inheritance. With no doubt, the legacy of Bennett in scientific inquiry and mentorship will continue to inspire future generations.