About

Kenneth S. Kosik is a Distinguished Professor of Molecular, Cellular, and Developmental Biology at the University of California, Santa Barbara. He completed a B.A. and M.A. in English literature from Case Western Reserve University in 1972 and earned an M.D. from the Medical College of Pennsylvania in 1976. Following his medical training, he served as a resident in neurology at Tufts New England Medical Center, where he was Chief Resident in 1980. He held academic appointments at Harvard Medical School beginning in 1980, achieving the rank of full professor in 1996, and also held positions at McLean Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, and the Dana-Farber Cancer Institute. In 2004, Kosik joined UC Santa Barbara as the Harriman Professor of Neuroscience Research and Co-Director of the Neuroscience Research Institute. He was elected a Fellow of the American Association for the Advancement of Science in 2017. His research focuses on fundamental biological processes related to the brain, including its development, diseases, and evolution. His lab emphasizes collaborative, reductionist approaches centered on genes, molecules, and cells, while also incorporating systems-level informatic studies involving genomic, transcriptional, and electrophysiologic data. Key themes include how cells acquire and lose their identities, synaptic plasticity, and proteostasis, with particular interest in how protein translation at the synapse influences learning and how impairments in plasticity contribute to neurodegenerative diseases.

Research topics

• Biology
• Neuroscience
• Biochemistry
• Cell biology
• Computer Science
• Genetics
• Anatomy
• Biophysics
• Chemistry
• Medicine
• Pathology
• Physics
• Computational biology
• Internal medicine

Selected publications

• Systematic analysis of RhoGAP expression and function in border cell morphology and migration

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-04-08

  articleOpen access

  Abstract Rho family GTPases are central hubs in the signaling and cytoskeletal networks that govern cell morphology and behavior. GTPase-activating proteins (GAPs) inactivate them by accelerating GTP hydrolysis. However, a systematic analysis of GAPs in cell migration is lacking. Here, we report screens for RhoGAP expression and function in migratory Drosophila border cells. Constitutively active Cdc42, Rac, or Rho causes defects, demonstrating that negative regulation is critical. Integrating single-cell RNAseq with published datasets reveals that most of the 22 RhoGAPs are expressed in border cells. RNAi knockdown shows most RhoGAPs are functionally required. We developed automated image analysis tools to sensitively and objectively classify border cell morphologies, defining a normal morphological phase space. RhoGAP perturbations push clusters outside this range. In-depth analysis of RhoGAPp190 reveals that loss-of-function resembles Rho hyperactivation and gain-of-function resembles myosin II inhibition. Thus, complex spatiotemporal sculpting of RhoGTPase activities requires diverse RhoGAPs within a single cell type to control morphology and motility in vivo .

  PublisherOA PDFDOI

• A recurrent neural network model of chronic pain development and recovery

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-04-22

  articleOpen access

  Abstract Chronic pain presents a leading challenge in the world today for both clinicians and researchers. Because chronic pain is difficult to explain and treat, it is often managed with opioids despite providing limited relief and contributing to dependence and misuse. Persistent pain can be maintained by altered central nervous system processing even in the absence of distinct tissue damage or disease, which may limit the efficacy of conventional pharmacological therapies that target nociceptive signal transmission rather than maladaptive central nervous system dynamics often present in those with chronic pain. Although neuroimaging studies have identified this shift from nociceptive to emotional circuits during pain chronification, a quantitative framework linking these neural changes to longitudinal pain trajectories or recovery is lacking. We present a parsimonious firing-rate model that can account for the development of and recovery from chronic pain, which is based on the theoretical framework established by Wilson and Cowan. The model provides a quantitative explanation of how sensitization, anxiety, and fear maintain pain even after an injury has healed, and how calming stimulus downregulates these processes to facilitate recovery. A study applying the same principles as the model produced an average pain decrease of 3.5 on the Visual Analog Scale (VAS), with all subjects experiencing a reduction in pain. These results, coupled with our model and findings in prior studies, suggest that increasing calming stimulus can reduce pain without necessitating pharmacological or invasive, resource-intensive interventions.

  PublisherDOI

• BAG2 Condensates Couple Proteostasis to CD8 ⁺ T Cell Surveillance

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-04-27

  articleOpen access

  SUMMARY Protein aggregation, impaired degradation, and immune activation are central hallmarks of neurodegenerative diseases, yet how these processes are coordinated remains unclear. Here, we identify Immune-Protein Degradation Bodies (I-PDBs), a previously unrecognized class of BAG2-driven, phase-separated organelles that integrate protein quality control with adaptive immunity. IFNγ induce I-PDB formation at the endoplasmic reticulum (ER), where they concentrate immunoproteasome components, MHC-I peptide-loading machinery, and ER-associated chaperones. I-PDBs redirect proteostatic cargo from centrosomal aggregation pathways to spatially restricted degradation sites optimized for antigenic peptide generation, coupling selective substrate clearance to CD8⁺ T cell engagement. Using a cellular model of aggregation-prone tau, we show that I-PDBs capture pathological tau fibrils at ER–microtubule interfaces and process them into potentially antigenic peptides, thus reducing the load of aggregation-prone tau peptides. We term this mechanism the Proteostasis-Associated Immune Relay (PAIR), establishing I-PDBs as critical hubs linking proteostasis to immune surveillance with broad implications for disease. Graphical Abstract Highlights IFNγ drives BAG2-dependent Immune-Protein Degradation Bodies (I-PDBs) I-PDBs assemble at the endoplasmic reticulum and are enriched in immunoproteasome and MHC-I machinery I-PDBs shunt misfolded proteins, including pathological tau, away from aggresomes I-PDBs couple proteostasis to antigen presentation, enhancing CD8⁺ T cell recognition The Proteostasis-Associated Immune Relay (PAIR) defines a pathway linking proteostasis to adaptive immunity

  PublisherDOI

• Preconfigured neuronal firing sequences in human brain organoids

  Nature Neuroscience · 2025-11-24 · 7 citations

  articleOpen access
  PublisherOA PDFDOI

• Protein-Like Polymer for Inhibition of Tau Fibril Propagation in Human-Derived Models of Neurodegeneration

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-02-03

  preprintSenior authorCorresponding

  Abstract The misfolding, aggregation, and spread of tau protein fibrils underlie tauopathies, a diverse class of neurodegenerative diseases for which effective treatments remain elusive. Among these are corticobasal dementia (CBD) and progressive supranuclear palsy (PSP), canonical examples of 4-repeat (4R) tauopathies characterized by tau isoforms exclusively with four microtubule-binding repeat domains. We target this 4R tau isoform-specific mechanism by focusing on misfolded tau’s distinctive stem-loop-stem structural motif formed by the junction of the 4R-defining alternatively spliced exon and the adjacent constitutive exon. A synthetic peptide based on this stem-loop-stem sequence can induce aggregation and spread in an isoform-specific manner. Here, we develop a protein-like polymer (PLP) in which multiple copies of this synthetic peptide form a brush-like structure capable of preventing tau aggregation by binding and capping fibril ends in vitro , in human brain organoids, and in cellular models with an EC50 of 105 ± 14 nM. PLPs demonstrate robust activity against fibrils derived from CBD and PSP patient brains and a PS19 mouse tauopathy model. Previous tau-targeted treatments have primarily focused on broad tau clearance, aggregation inhibition, or microtubule stabilization, often lacking isoform specificity and precision. In contrast, this approach targets the 4R tau isoform’s unique structural motif, offering a tailored therapeutic intervention for diseases like CBD and PSP. Supported by prior studies showing blood-brain barrier penetrance and safety profiles, this tau-binding PLP offers a promising translational path toward clinical applications in tauopathy treatment.

  PublisherDOI

• Genetic Contributions to Alzheimer's Disease and Frontotemporal Dementia in Admixed Latin American Populations

  Research Square · 2025-05-06

  preprintOpen access
  PublisherOA PDFDOI

• Tracking tau and cellular responses in human iPSC-microglia from uptake to seedable secretion in extracellular vesicles

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-07-21

  preprintOpen access

  Abstract The templated spread of tau aggregates in tauopathies has been attributed to neuron-to- neuron spread, but microglia have also been implicated through mouse studies. Here we examine in detail the uptake, processing, release and seeding of tau using human iPS- derived microglia (iMGL). We show that tau is taken up by iMGL via LRP1 and heparan sulfate proteoglycans, with a role for LRRK2 in LRP1 trafficking, and that phagocytosed fibrils can escape into the cytoplasm. Monomeric tau has minimal effects on iMGL, but recombinant or brain-derived tau fibrils induce a shift towards chemokine and interferon response subtypes, alongside downregulation of homeostatic and MHC genes. Endogenous tau protein is undetectable in iMGL, and monomeric internalised tau is digested to completion, but fibrillar tau is more resistant to degradation and becomes phosphorylated on two specific residues. Finally, fibrillar tau is released by iMGL, visualized within extracellular vesicles by cryo-EM, and can seed tau aggregation in downstream neurons.

  PublisherOA PDFDOI

• A wireless subdural-contained brain–computer interface with 65,536 electrodes and 1,024 channels

  Nature Electronics · 2025-12-08 · 7 citations

  articleOpen access
  PublisherOA PDFDOI

• Driving research on successful aging and neuroprotection in Latin America: Insights from the inaugural symposium on brain resilience and healthy longevity

  Alzheimer s & Dementia · 2025-03-01 · 2 citations

  reviewOpen access

  INTRODUCTION: Global life expectancy has steadily increased in recent decades, resulting in a significant rise in the number of individuals aged 80 years and older. This trend is also evident in Latin America, where life expectancy is improving, though at varying rates across countries and regions. METHODS: Partnering with the Neurosciences Group of Antioquia (GNA), we launched a Colombian study on resilience in families with autosomal dominant Alzheimer's disease and the oldest-old population. Over the past 2 years, the project has expanded to include participants from Peru, Chile, and Costa Rica. RESULTS: This research led to the first symposium on Brain Resilience and Healthy Longevity, held in Medellín, Colombia, in August 2024. DISCUSSION: The article summarizes key discussions from the symposium, highlighting the most promising opportunities for brain resilience and prevention research in the region and offering recommendations for future research to promote healthy aging and dementia-free communities. HIGHLIGHTS: Uncovering the genetic and physiological drivers of cognitive resilience, neurodegeneration resistance, and healthy longevity is essential for maintaining brain function as we age. "Superagers" and cognitively resilient individuals from Latin American families with Alzheimer's disease offer valuable insights into brain protection mechanisms. Studying the interplay of socio-environmental and genetic factors in the oldest-old is key to understanding healthy longevity and improving dementia prevention. The inaugural Brain Resilience and Healthy Longevity Symposium highlights the need for global collaboration to uncover factors that drive cognitive resilience and healthy aging in Latin America, advancing dementia prevention.

  PublisherOA PDFDOI

• Protective mechanisms against Alzheimer’s Disease in APOE3-Christchurch homozygous astrocytes

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-01-21

  preprintOpen accessSenior authorCorresponding

  Abstract The APOE3-Christchurch (APOE3-Ch) variant has been linked to reduced Alzheimer’s Disease (AD) risk, but its protective mechanisms remain unclear. This study explores the neuroprotective phenotype of APOE3-Ch astrocytes, focusing on lipid metabolism and tau processing. APOE3-Ch astrocytes demonstrate enhanced tau oligomer uptake via HSPG- and LRP1-mediated pathways, facilitated by elevated HSPG expression, and achieve superior tau degradation through lysosomal pathways and proteasomal pathways, in contrast to wild-type astrocytes, which primarily use proteasomal mechanisms. Transcriptomic analysis reveals upregulation of genes involved in endocytosis and cell projection assembly, explaining enhanced tau uptake and clearance in APOE3-Ch astrocytes. Lipidomic profiling identifies reduced levels of pathological lipids such as ceramides and gamma-linolenic acid (GLA), potentially mitigating neuroinflammation. These findings provide insight into the protective mechanisms of APOE3-Ch astrocytes and underscore their potential as therapeutic targets for tauopathy and neurodegeneration in AD. Teaser APOE3-Christchurch astrocytes enhance tau clearance and mitigate neurotoxic lipid accumulation, unveiling protective mechanisms against Alzheimer’s.

  PublisherDOI

Recent grants

• NIH Grant R01AG006601

  NIH · $3.0M · 2002

• Project 1: Aberrant neuronal activity and tau distribution in FTD

  NIH · $21.6M · 2016–2023

• NIH Grant R21NS045327

  NIH · $411k · 2005

• NIH Grant U01AG033931

  NIH · $4.3M · 2012

• NIH Grant R01AG005538

  NIH · $17k · 1985

Frequent coauthors

• Eric M. Reiman

  Arizona Alzheimer’s Consortium

  79 shared

• Dennis J. Selkoe

  Harvard University

  75 shared

• Francisco Lopera

  61 shared

• Yakeel T. Quiroz

  Harvard University

  53 shared

• Anna M. Krichevsky

  Brigham and Women's Hospital

  53 shared

• Juliana Acosta‐Uribe

  Universidad de Antioquia

  44 shared

• Joseph F. Arboleda‐Velásquez

  43 shared

• David Aguillón

  Universidad de Antioquia

  42 shared

Labs

• Kosik LabPI

  Not provided

Education

• B.A., English literature

  Case Western Reserve University

  1972

• M.A., English literature

  Case Western Reserve University

  1972

• M.D.

  Medical College of Pennsylvania

  1976

Awards & honors

• American Association for the Advancement of Science Fellow (…