Cavin-1 is linked to lipid droplet formation in human hepatic stellate cells

  • Hiroaki YokomoriEmail author
  • Wataru Ando
  • Masaya Oda
Letter to the Editor

Caveolin-1 (CAV-1), discovered using immunohistocytochemistry as a major component of caveolae localized in plasma membrane caveolae, Golgi apparatus, and trans-Golgi-derived transport vesicles, is expressed either as a soluble cytoplasmic form or as a secreted form, depending on the cell type [1]. Polymerase I and transcript release factor (PTRF)/cavin-1 selectively associate with mature caveolae at the plasma membrane but not Golgi-localized CAV. Interaction of cavin-1 with CAV-1 is not direct, but is possibly mediated through cytoskeletal interactions between microtubules and actin filaments [2].

Lipid droplets (LDs), which originate from the ER surface, are constantly forming, growing, and shrinking [3]. According to the biogenesis of caveolae and LD, the process initiates by synthesis of CAV-1 in the endoplasmic reticulum (ER), followed by its exit to Golgi, where it buds as vesicles and ultimately fuses with the plasma membrane, where it can acquire additional proteins including...


Supplementary material

795_2019_219_MOESM1_ESM.tif (19.7 mb)
Supplemental Fig. 1 Transmission electron micrographs of CAV-1 (a, b, e, f) showing hepatic stellate cells (HSCs) around the portal tract (a, b) and around the central vein (c, d) in normal liver tissue (a–d) and in cirrhotic liver tissue (e, f): a, c, e low magnification; b, d, f high magnification. a, b: HSCs associated with low-density lipid droplets (LDs). Immunogold particles labeled CAV-1 in small clusters (arrowheads) on the rims of low-density LDs. Arrowheads indicate CAV-1 in the rim. c, d: Immunogold particles labeled CAV-1 in vesicles (black arrowheads) on the rims of low-density, Golgi complex (white arrowheads), and caveolae (white arrowheads). Bars = 2 μm or 200 nm. e, f: Immunogold particle labeling of CAV-1 on ER-like membranes attached to LDs. HSC, hepatic stellate cell. Arrowheads indicate CAV-1-positive particles. Black arrowheads indicate caveolae; white arrows indicate ER-like membranes (TIF 20131 KB)


  1. 1.
    Gupta R, Toufaily C, Annabi B (2014) Caveolin and cavin family members: dual roles in cancer. Biochimie 107(Pt B):188–202CrossRefPubMedGoogle Scholar
  2. 2.
    Hill MM, Bastiani M, Luetterforst R, Kirkham M, Kirkham A, Nixon SJ, Walser P, Abankwa D, Oorschot VM, Martin S, Hancock JF, Parton RG (2008) PTRF-Cavin, a conserved cytoplasmic protein required for caveola formation and function. Cell 132:113–124CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Fujimoto T, Parton RG (2011) Not just fat: the structure and function of the lipid droplet. Cold Spring Harb Perspect Biol 3:a004838CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Hayer A, Stoeber M, Bissig C, Helenius A (2010) Biogenesis of caveolae: stepwise assembly of large caveolin and cavin complex. Traffic 11:361–382CrossRefPubMedGoogle Scholar
  5. 5.
    Pol A, Luetterforst R, Lindsay M, Heino S, Ikonen E, Parton RG (2001) A caveolin dominant negative mutant associates with lipid bodies and induces intracellular cholesterol imbalance. J Cell Biol 152:1057–1070CrossRefPubMedPubMedCentralGoogle Scholar
  6. 6.
    Briand N, Prado C, Mabilleau G, Lasnier F, Le Lièpvre X, Covington JD, Ravussin E, Le Lay S, Dugail I (2014) Caveolin-1 expression and cavin stability regulate caveolae dynamics in adipocyte lipid store fluctuation. Diabetes 63:4032–4044CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Friedman SL (2008) Hepatic stellate cells: protean, multifunctional, and enigmatic cells of the liver. Physiol Rev 88:125–172CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    Yokomori H, Ando W, Oda M (2018) Caveolin-1 is related to lipid droplet formation in hepatic stellate cells in human liver. Acta Histochem. PubMedGoogle Scholar
  9. 9.
    Yamazaki H, Oda M, Takahashi Y, Iguchi H, Yoshimura K, Okada N, Yokomori H (2013) Relation between ultrastructural localization, changes in caveolin-1, and capillarization of liver sinusoidal endothelial cells in human hepatitis C-related cirrhotic liver. J Histochem Cytochem 61:169–176CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Singh S, Liu S, Rockey DC (2016) Caveolin-1 is upregulated in hepatic stellate cells but not sinusoidal endothelial cells after liver injury. Tissue Cell 48:126–132CrossRefPubMedGoogle Scholar
  11. 11.
    Corpechot C, Barbu V, Wendum D, Kinnman N, Rey C, Poupon R, Housset C, Rosmorduc O (2002) Hypoxia-induced VEGF and collagen I expressions are associated with angiogenesis and fibrogenesis in experimental cirrhosis. Hepatology 35:1010–1021CrossRefPubMedGoogle Scholar
  12. 12.
    Wang Y, Roche O, Xu C, Moriyama EH, Heir P, Chung J, Roos FC, Chen Y, Finak G, Milosevic M, Wilson BC, Teh BT, Park M, Irwin MS, Ohh M (2012) Hypoxia promotes ligand-independent EGF receptor signaling via hypoxia-inducible factor-mediated upregulation of caveolin-1. Proc Natl Acad Sci USA 109:4892–4897CrossRefPubMedGoogle Scholar

Copyright information

© The Japanese Society for Clinical Molecular Morphology 2019

Authors and Affiliations

  1. 1.Department of Internal MedicineKitasato University Medical CenterSaitamaJapan
  2. 2.Department of Clinical Pharmacy, School of PharmacyKitasato UniversityTokyoJapan
  3. 3.Organized Center of Clinical MedicineInternational University of Health and WelfareTokyoJapan

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