title: Autolysosome biogenesis and developmental senescence are regulated by both Spns1 and v-ATPase.
abstract: Spns1 (Spinster homolog 1 [Drosophila]) in vertebrates, as well as Spin (Spinster) in Drosophila, is a hypothetical lysosomal H+-carbohydrate transporter, which functions at a late stage of macroautophagy (hereafter autophagy). The Spin/Spns1 defect induces aberrant autolysosome formation that leads to developmental senescence in the embryonic stage and premature aging symptoms in adulthood. However, the molecular mechanism by which loss of Spin/Spns1 leads to the specific pathogenesis remains to be elucidated. Using chemical, genetic and CRISPR/Cas9-mediated genome-editing approaches in zebrafish, we investigated and determined a mechanism that suppresses embryonic senescence as well as autolysosomal impairment mediated by Spns1 deficiency. Unexpectedly, we found that a concurrent disruption of the vacuolar-type H+-ATPase (v-ATPase) subunit gene, atp6v0ca (ATPase, H+transporting, lysosomal, V0 subunit ca) led to suppression of the senescence induced by the Spns1 defect, whereas the sole loss of Atp6v0ca led to senescent embryos similar to the single spns1 mutation. Moreover, we discovered that the combined stable defect seen in the presence of both the spns1 and atp6v0ca mutant genes still subsequently induced premature autophagosome-lysosome fusion marked by insufficient acidity, while extending developmental life span, compared with the solely mutated spns1 defect. Our data suggest that Spns1 and the v-ATPase orchestrate proper autolysosomal biogenesis with optimal acidification that is critically linked to developmental senescence and survival.
authors.affiliation: a Department of Metabolism & Aging , The Scripps Research Institute , Jupiter , FL , USA.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Sasaki
authors.affiliation: a Department of Metabolism & Aging , The Scripps Research Institute , Jupiter , FL , USA.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lian
authors.affiliation: a Department of Metabolism & Aging , The Scripps Research Institute , Jupiter , FL , USA.|b Department of Pharmacy , University of Rajshahi , Rajshahi , Bangladesh.
authors.forename: Alam
authors.initials: A
authors.lastname: Khan
authors.affiliation: c Department of Biomedical Genetics , University of Rochester Medical Center , Rochester , NY , USA.
authors.forename: Jesse R
authors.initials: JR
authors.lastname: Llop
authors.affiliation: c Department of Biomedical Genetics , University of Rochester Medical Center , Rochester , NY , USA.
authors.forename: Andrew V
authors.initials: AV
authors.lastname: Samuelson
authors.affiliation: d Department of Molecular Physiology and Biophysics , Vanderbilt University School of Medicine , Nashville , TN , USA.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Chen
authors.affiliation: e Life Sciences Institute, Department of Molecular, Cellular, and Developmental Biology , University of Michigan , Ann Arbor , MI , USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Klionsky
authors.affiliation: a Department of Metabolism & Aging , The Scripps Research Institute , Jupiter , FL , USA.
authors.forename: Shuji
authors.initials: S
authors.lastname: Kishi
mesh_terms: D000818:Animals; D001343:Autophagy; D001483:Base Sequence; D015415:Biomarkers / Q000378:metabolism; D064113:CRISPR-Cas Systems / Q000235:genetics; D016922:Cellular Senescence; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D008136:Longevity; D008247:Lysosomes / Q000378:metabolism*; D008561:Membrane Fusion; D008565:Membrane Proteins / Q000378:metabolism*; D010588:Phagosomes / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D016019:Survival Analysis; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism*; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics; D029961:Zebrafish Proteins / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D008565:Membrane Proteins; D029961:Zebrafish Proteins; C454859:spns1 protein, zebrafish; D025262:Vacuolar Proton-Translocating ATPases; D006180:Proton-Translocating ATPases; C000624980:Atp6v0ca protein, zebrafish
keywords: aging; autophagy; lysosome; senescence; spinster; vacuolar-type H+-ATPase; zebrafish