title: A nanobuffer reporter library for fine-scale imaging and perturbation of endocytic organelles.
abstract: Endosomes, lysosomes and related catabolic organelles are a dynamic continuum of vacuolar structures that impact a number of cell physiological processes such as protein/lipid metabolism, nutrient sensing and cell survival. Here we develop a library of ultra-pH-sensitive fluorescent nanoparticles with chemical properties that allow fine-scale, multiplexed, spatio-temporal perturbation and quantification of catabolic organelle maturation at single organelle resolution to support quantitative investigation of these processes in living cells. Deployment in cells allows quantification of the proton accumulation rate in endosomes; illumination of previously unrecognized regulatory mechanisms coupling pH transitions to endosomal coat protein exchange; discovery of distinct pH thresholds required for mTORC1 activation by free amino acids versus proteins; broad-scale characterization of the consequence of endosomal pH transitions on cellular metabolomic profiles; and functionalization of a context-specific metabolic vulnerability in lung cancer cells. Together, these biological applications indicate the robustness and adaptability of this nanotechnology-enabled 'detection and perturbation' strategy.
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.|Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Chensu
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Yiguang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Bodemann
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Tian
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Xinpeng
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Huang
authors.affiliation: Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Zeping
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: DeBerardinis
authors.affiliation: Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: White
authors.affiliation: Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
authors.forename: Jinming
authors.initials: J
authors.lastname: Gao
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D017209:Apoptosis; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism / Q000648:ultrastructure; D002460:Cell Line; D045744:Cell Line, Tumor; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism / Q000648:ultrastructure*; D005456:Fluorescent Dyes; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008175:Lung Neoplasms / Q000378:metabolism / Q000648:ultrastructure; D008247:Lysosomes / Q000378:metabolism / Q000648:ultrastructure*; D000076222:Mechanistic Target of Rapamycin Complex 1; D055442:Metabolome; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D046912:Multiprotein Complexes / Q000378:metabolism; D053758:Nanoparticles; D015388:Organelles / Q000648:ultrastructure; D011506:Proteins / Q000378:metabolism; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D014617:Vacuoles / Q000648:ultrastructure
chemical_list: D000596:Amino Acids; D005456:Fluorescent Dyes; D046912:Multiprotein Complexes; D011506:Proteins; D000076222:Mechanistic Target of Rapamycin Complex 1; D058570:TOR Serine-Threonine Kinases