Klaudiusz Robert Weiss (1944 – 2022)
Nationality. American
Academic career. Ph.D. Stony Brook University, NY. Postdoctoral fellow, Assistant, and Associate Professor, Columbia University, NYC. Professor of Neuroscience, Icahn School of Medicine, NYC
Institution. Mount Sinai Medical Center, NYC.
Field. Neuroscience
Influensers. Jerzy Konorski, Irving Kupfermann
Klaudiusz Robert Weiss was Henry and Lillian Stratton's Professorial Chair and Professor of Neuroscience at the Icahn School of Medicine at Mount Sinai in New York. Weiss published over 200 scientific papers on the cellular and neuronal mechanisms of innate and acquired behaviors in the marine animal Aplysia Californica. Together with Irving Kupfermann, he published an influential review “The Command Neuron Concept” which became a Citation Classic [1]. Weiss closely collaborated over many years with Irving Kupfermann’s research group until Kupfermann passed in 2002.
Scientific career. Weiss received his Ph.D. in experimental psychology from Stony Brook University in 1973 and did his postdoctoral training in Irving Kupfermann’s laboratory in the Center for Neurobiology and Behavior at Columbia University in New York City. At Columbia University Weiss progressed to Assistant and then Associate Professor, and in 1991 he moved to the Icahn School of Medicine at Mount Sinai as a tenured Professor of Neuroscience.
Awards and distinctions. Weiss received a McKnight Foundation Investigator Award, MERIT, and Senior Scientist Awards from the National Institutes of Health (NIH), and was elected as a Fellow by the American Association for the Advancement of Science and the Association for Psychological Science. NIH grants continuously funded his research.
Early life and education. Klaudiusz Robert Weiss was born in France to Polish-Jewish parents who returned to Poland in 1953. After elementary education in Italy and Poland and a Technical High School diploma, Weiss studied Sociology and Psychology at the University of Warsaw, graduating with a Master’s degree diploma in Sociology in 1967. He became interested in behavioral neurobiology and in 1970 received a Ph.D. Scholarship at the Nencki Institute of Experimental Biology of the Polish Academy of Sciences headed by Professor Jerzy Konorski. Due to political upheavals and the anti-Semitic campaign in Poland, Weiss immigrated to the USA in 1971. He continued his studies at Stony Brook University, completing a Ph.D. degree in experimental psychology in 1973.
Research. As a postdoctoral fellow, Weiss was introduced to the model system that was the subject of most of his subsequent research. This system mediates feeding behavior in the mollusk Aplysia Californica, and has several experimentally advantageous features that as a whole are not found in other organisms. Weiss’ most notable postdoctoral work focused on a large neuron that contains the neurotransmitter serotonin. With his mentor (Irving Kupfermann) Weiss conducted a series of behavioral, physiological, and biochemical studies that played a key role in developing the now very familiar concept of neuromodulation [2-4]. This research was amongst the first that established cyclic adenosine monophosphate (cAMP) [5] as a second messenger utilized as a neurotransmitter (rather than a hormone). As an independent scientist, Weiss’ early research was conducted at a neuromuscular junction of Aplysia. Weiss used this system to study that are co-released with the classical neurotransmitter, acetylcholine. His work challenged existing orthodoxies that held that peptide transmission occurs under extreme conditions, e.g., stress or strong stimulation. Weiss showed that peptides are released and exert important actions when neurons fire in their normal physiological ranges [5-9]. In later years, Weiss focused on the neural network that mediates feeding and drew heavily on his background in Psychology. He characterized mechanisms responsible for the repetition priming that is observed as behavior is repeated and demonstrated that it can be an automatic consequence of the release of intrinsic neuromodulators [10-11]. He showed that this can have both expected and unexpected consequences for subsequent task switching [12].
References:
1. Kupfermann I., and K.R.Weiss. The Command Neuron Concept. Behavioral and Brain Sciences 1978, 1 (01):3,10, DOI:10.1017/50140525X00059057. 2. Weiss K.R., Cohen J.L., and I.Kupfermann. Potentiation of muscle contraction: a possible modulatory function of an identified serotonergic cell in Aplysia. Brain Res. 1975 Dec 5;99(2): 381-6. DOI:10.1016/0006-8993(75)90041-4. PubMed PMID: 1182556. 3. Weiss K.R., Cohen J.L., and I.Kupfermann. Modulatory control of buccal musculature by a serotonergic neuron (metacerebral cell) in Aplysia. J Neurophysiol. 1978 Jan;41(1):181-203. DOI:10.1152/jn.1978.41.1.181. PubMed PMID: 621542. 4. Weiss K.R., E., Schonberg, M., Mandelbaum, D.E., and I. Kupfermann. Activity of an individual serotonergic neuron in Aplysia enhances the synthesis of cyclic adenosine monophosphate. Nature 1978 April 20; 272 (5655): 727-728. PubMed PMID: 205757. 5. Weiss K.R., E., Schonberg, M., Mandelbaum, D.E., and I. Kupfermann. Activity of an individual serotonergic neuron in Aplysia enhances the synthesis of cyclic adenosine monophosphate. Nature 1978 April 20; 272 (5655): 727-728. PubMed PMID: 20575 6. Kupfermann I., and K.R. Weiss. The activity of an identified serotonergic neuron in free-moving Aplysia correlates with behavioral arousal. Brain Res. 1982 Jun 10:241(2):334-337. PubMed PMID 7104716. 7. Cropper E.C., Lloyd P.E., Reed W., Tenenbaum R., Kupfermann I., and K. R. Weiss. Multiple neuropeptides in cholinergic motor neurons of Aplysia: evidence for modulation intrinsic to the motor circuit. PNAS 1987. August; 84(10):3486-3490. PubMed PMID 3472218. 8. Cropper E.C., Tenenbaum R., Kolks M.A., Kupfermann I., and K. R. Weiss. Myomodulin: a bioactive neuropeptide present in an identified cholinergic buccal motor neuron of Aplysia PNAS 1987.August 84(15):5483-6. PubMed PMID 3474664. 9. Cropper E.C., Price D., Tenenbaum R., Kupfermann I., and K. R. Weiss. Release of peptide co-transmitters from a cholinergic motor neuron under physiological conditions. PNAS 1990 Feb 87(3):933-93. PubMed PMID 2153979. 10. Dacks A.M., Siniscalchi M.J., and K. R. Weiss. Removal of default state-associated inhibition during repetition priming improves response articulation-PubMed PMID 23223294. 11. Cropper E.C., Friedman A.K., Jing J., Perkins M.H., and K. R. Weiss. Neuromodulation as a mechanism for the induction of repetition priming. Curr Opin Neurobiol 2014 Dec;29:33-38. PubMed PMID 25261622. 12. Friedman A.K., and K. R. Weiss Repetition priming of motoneuronal activity in a small motor network: intercellular and intracellular signaling. J Neurosci 2010 Jun 30;30(26):8906-8919. PubMed ID 20592213,