title: The elastin peptide (VGVAPG)3 induces the 3D reorganisation of PML-NBs and SC35 speckles architecture, and accelerates proliferation of fibroblasts and melanoma cells.
abstract: During melanoma tumour growth, cancerous cells are exposed to the immediate surrounding the micro- and macro environment, which is largely modified through the degradation of the extracellular matrix by fibroblast-derived metalloproteinases. Among the degradation products, (VGVAPG)3, an elastin peptide is known to stimulate the proliferation of both fibroblasts and cancerous cells by binding to the elastin-binding receptor and activating the MEK/ERK signal transduction pathway. As this process strongly modifies mRNA synthesis, we investigated its effect on the relative three-dimensional organisation of the major partners of the mRNA splicing machinery: promyelocytic nuclear bodies (PML-NBs ) and splicing component 35 speckles (SC35) of normal fibroblasts and melanoma SK-MEL-28 cells. SC35 and PML-NBs proteins were immunolabeled and imaged by confocal microscopy within these cells cultured with (VGVAPG)3. Three-dimensional reconstruction was performed to elucidate the organisation of PML-NBs and SC35 speckles and their spatial relationship. In G0 cells, SC35 speckles were sequestered in PML-NBs. Shortly after (VGVAPG)3 stimulation, the three-dimensional organisation of PML-NBs and SC35 speckles changed markedly. In particular, SC35 speckles gradually enlarged and adopted a heterogeneous organisation, intermingled with PML-NBs. Conversely, inhibition of the elastin-binding protein or MEK/ERK pathway induced a remarkable early sequestration of condensed SC35 speckles in PML-NBs, the hallmark of splicing inhibition. The 3D architecture of speckles/PML-NBs highlights the modulation in their spatial relationship, the multiple roles of PML-NBs in activation, inhibition and sequestration, and provides the first demonstration of the dependence of PML-NBs and SC35 speckles on the elastin peptide for these functions.
authors.affiliation: UMR CNRS 7369 MEDyC, SFR Cap-Santé, URCA, Reims, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Chatron-Colliet
authors.forename: Nathalie
authors.initials: N
authors.lastname: Lalun
authors.forename: Christine
authors.initials: C
authors.lastname: Terryn
authors.forename: Sandrine
authors.initials: S
authors.lastname: Kurdykowski
authors.forename: Marianne
authors.initials: M
authors.lastname: Lorenzato
authors.forename: Anthony
authors.initials: A
authors.lastname: Rusciani
authors.forename: Dominique
authors.initials: D
authors.lastname: Ploton
authors.forename: Laurent
authors.initials: L
authors.lastname: Duca
authors.forename: Hélène
authors.initials: H
authors.lastname: Bobichon
mesh_terms: D000328:Adult; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D004549:Elastin / Q000737:chemistry*; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008545:Melanoma / Q000473:pathology*; D009842:Oligopeptides / Q000494:pharmacology*; D012326:RNA Splicing / Q000187:drug effects*; D013329:Structure-Activity Relationship
chemical_list: D009842:Oligopeptides; D004549:Elastin; C042635:valyl-glycyl-valyl-alanyl-prolyl-glycine