Biology subjects

Cantley, L.

Publications and source records attributed to Cantley, L..

5 recordsLinked to original sources

bioRxiv2026

Mitochondrial redox potential couples to single-cell mass in a conserved sublinear scaling law, modulated by mitochondrial mass-control genes

Using quantitative phase microscopy and genetically-encoded metabolism probes, we simultaneously measured single-cell dry mass and mitochondrial redox efficiency across eukaryotic cell types. We discovered that single-cell mass scales with mitochondrial redox efficiency, according to a sublinear power law, across budding yeast, mouse, and human cells. Genetic and pharmacological perturbations of mitochondrial redox balance shifted the coefficient k and exponent y predictably, while preserving the scaling law, indicating a causative coupling between biomass accrual and mitochondrial redox efficiency. We also discovered that both single-cell mass and mitochondrial redox efficiency manifest log-normal distributions, providing more support for previous theories that biomass accrual is an exponential process, meaning the rate of mass increase depends on the current mass. Finally, our yeast knockout screen identified 81 mass control genes (MCGs) that disrupted the log-normality of single-cell mass. Interestingly, MCGs were enriched for mitochondrial metabolism and cristae maintenance, whereas <10% were related to the cell cycle. Conserved MCGs, including human TRIAP1, ATPAF1, and ACO1, also maintained human single-cell mass log-normality and sublinear scaling with mitochondrial redox efficiency. These findings reveal a shared bioenergetic principle at the single-cell level, and new techniques to study it. This scaling law provides a quantitative framework for understanding cell mass control, metabolic coupling, and disease-associated growth regulation.

cell biology↗

bioRxiv2024

Parallel phosphoproteomics and metabolomics map the global metabolic tyrosine phosphoproteome

Tyrosine phosphorylation of metabolic enzymes is an evolutionarily conserved post-translational modification that facilitates rapid and reversible modulation of enzyme activity, localization or function. Despite the high abundance of tyrosine phosphorylation events detected on metabolic enzymes in high-throughput mass spectrometry-based studies, functional characterization of tyrosine phosphorylation sites has been limited to a subset of enzymes. Since tyrosine phosphorylation is dysregulated across human diseases, including cancer, understanding the consequences of metabolic enzyme tyrosine phosphorylation events is critical for informing disease biology and therapeutic interventions. To globally identify metabolic enzyme tyrosine phosphorylation events and simultaneously assign functional significance to these sites, we performed parallel phosphoproteomics and polar metabolomics in non-tumorigenic mammary epithelial cells (MCF10A) stimulated with epidermal growth factor (EGF) in the absence or presence of the epidermal growth factor receptor (EGFR) inhibitor erlotinib. We performed an integrated analysis of the phosphoproteomic and metabolomic datasets to identify tyrosine phosphorylation sites on metabolic enzymes with functional consequences. We identified two previously characterized (PKM, PGAM1) and two novel (GSTP1, GLUD1) tyrosine phosphorylation sites on metabolic enzymes with purported functions based on metabolomic analyses. We validated these hits using a doxycycline-inducible CRISPR interference (CRISPRi) system in MCF10A cells, in which target metabolic enzymes were depleted with simultaneous re-expression of wild-type, phosphomutant or phosphomimetic isoforms. Together, these data provide a framework for identification, prioritization and characterization of tyrosine phosphorylation sites on metabolic enzymes with functional significance.

biochemistry↗

bioRxiv2023

LKB1 suppresses growth and promotes the internalization of EGFR through the PIKFYVE lipid kinase

The tumor suppressor LKB1 is a serine/threonine protein kinase that is frequently mutated in human lung adenocarcinoma (LUAD). LKB1 regulates a complex signaling network that is known to control cell polarity and metabolism; however, the pathways that mediate the tumor suppressive activity of LKB1 are incompletely defined. To identify mechanisms of LKB1- mediated growth suppression we developed a spheroid-based cell culture assay to study LKB1- dependent growth. Using this assay, along with genome-wide CRISPR screens and validation with orthogonal methods, we discovered that LKB1 suppresses growth, in part, by activating the PIKFYVE lipid kinase, which promotes the internalization of wild-type EGFR. Our findings reveal a new mechanism of regulation of EGFR, which may have implications for the treatment of LKB1-mutant LUAD.

cancer biology↗

bioRxiv2021

Cysteine induces mitochondrial reductive stress in glioblastoma through hydrogen peroxide production

Glucose and amino acid metabolism are critical for glioblastoma (GBM) growth, but little is known about the specific metabolic alterations in GBM that are targetable with FDA-approved compounds. To investigate tumor metabolism signatures unique to GBM, we interrogated The Cancer Genome Atlas for alterations in glucose and amino acid signatures in GBM relative to other human cancers and found that GBM exhibits the highest levels of cysteine and methionine pathway gene expression of 32 human cancers. Treatment of patient-derived GBM cells with the FDA-approved cysteine compound N-acetylcysteine (NAC) reduce GBM cell growth and mitochondrial oxygen consumption, which was worsened by glucose starvation. Mechanistic experiments revealed that cysteine compounds induce rapid mitochondrial H2O2 production and reductive stress in GBM cells, an effect blocked by oxidized glutathione, thioredoxin, and redox enzyme overexpression. These findings indicate that GBM is uniquely susceptible to NAC-driven reductive stress and could synergize with glucose-lowering treatments for GBM.

cancer biology↗

bioRxiv2020

Distribution and localization of phosphatidylinositol 5-phosphate, 4-kinase alpha and beta in the brain

Phosphatidylinositol-4,5-bisphosphate (PI-4,5-P2) is critical for synaptic vesicle docking and fusion and generation of the second messengers, diacylglycerol and inositol-1,4,5-trisphosphate. PI-4,5-P2 can be generated by two families of kinases: type 1 phosphatidylinositol-4-phosphate 5-kinases, encoded by PIP5K1A, PIP5K1B and PIP5K1C, and type 2 phosphatidylinositol-5-phosphate 4-kinases, encoded by PIP4K2A, PIP4K2B, and PIP4K2C. While the roles of the type 1 enzymes in brain function have been extensively studied, the roles of the type 2 enzymes are poorly understood. Using selective antibodies validated by genetic deletion of pip4k2a or pip4k2b in mouse brain, we characterized the location of the enzymes, PI5P4K and PI5P4K{beta}, encoded by these genes. In mice, we demonstrate that PI5P4K is expressed in adulthood, whereas PI5P4K{beta} is expressed early in development. PI5P4K localizes to white matter tracts, especially the corpus callosum, and at a low level in neurons, while PI5P4K{beta} is expressed in neuronal populations, especially hippocampus and cortex. Dual labeling studies demonstrate that PI5P4K co-localizes with the oligodendrocyte marker, Olig2, whereas PI5P4K{beta} co-localizes with the neuronal marker, NeuN. Immunohistochemical subcellular distribution studies demonstrate that PI5P4K and PI5P4K{beta} are expressed in the early endosome system. Ultrastructural analysis demonstrates that both kinases are contained in axon terminals and dendritic spines adjacent to the synaptic membrane, which support a potential role in synaptic transmission. Immunohistochemical analysis of macaque and human brain tissue demonstrate a conserved pattern for PI5P4K and PI5P4K{beta}. These results highlight the diverse cell-autonomous expression of PI5P4K and PI5P4K{beta} and support further exploration into their role in synaptic function in the brain.

neuroscience↗