title: Procollagen Lysyl Hydroxylase 2 Expression Is Regulated by an Alternative Downstream Transforming Growth Factor β-1 Activation Mechanism.
abstract: PLOD2 (procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2) hydroxylates lysine residues in collagen telopeptides and is essential for collagen pyridinoline cross-link formation. PLOD2 expression and subsequent pyridinoline cross-links are increased in fibrotic pathologies by transforming growth factor β-1 (TGFβ1). In this report we examined the molecular processes underlying TGFβ1-induced PLOD2 expression. We found that binding of the TGFβ1 pathway related transcription factors SMAD3 and SP1-mediated TGFβ1 enhanced PLOD2 expression and could be correlated to an increase of acetylated histone H3 and H4 at the PLOD2 promoter. Interestingly, the classical co-activators of SMAD3 complexes, p300 and CBP, were not responsible for the enhanced H3 and H4 acetylation. Depletion of SMAD3 reduced PLOD2 acetylated H3 and H4, indicating that another as of yet unidentified histone acetyltransferase binds to SMAD3 at PLOD2. Assessing histone methylation marks at the PLOD2 promoter depicted an increase of the active histone mark H3K79me2, a decrease of the repressive H4K20me3 mark, but no role for the generally strong transcription-related modifications: H3K4me3, H3K9me3 and H3K27me3. Collectively, our findings reveal that TGFβ1 induces a SP1- and SMAD3-dependent recruitment of histone modifying enzymes to the PLOD2 promoter other than the currently known TGFβ1 downstream co-activators and epigenetic modifications. This also suggests that additional activation strategies are used downstream of the TGFβ1 pathway, and hence their unraveling could be of great importance to fully understand TGFβ1 activation of genes.
authors.affiliation: MATRIX Research Group, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; Epigenetic Editing Research Group, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands.
authors.forename: Rutger A F
authors.initials: RAF
authors.lastname: Gjaltema
authors.affiliation: MATRIX Research Group, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands.
authors.forename: Saskia
authors.initials: S
authors.lastname: de Rond
authors.affiliation: Epigenetic Editing Research Group, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands.
authors.forename: Marianne G
authors.initials: MG
authors.lastname: Rots
authors.affiliation: MATRIX Research Group, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands. Electronic address: r.a.bank@umcg.nl.
authors.forename: Ruud A
authors.initials: RA
authors.lastname: Bank
mesh_terms: D000107:Acetylation; D002478:Cells, Cultured; D006657:Histones / Q000378:metabolism; D006801:Humans; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D051900:Smad3 Protein / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
chemical_list: D006657:Histones; D018125:Receptors, Transforming Growth Factor beta; C497790:SMAD3 protein, human; D051900:Smad3 Protein; D016329:Sp1 Transcription Factor; D053773:Transforming Growth Factor beta1; C479138:PLOD2 protein, human; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I
keywords: E1A binding protein p300 (P300); SMAD transcription factor; epigenetics; fibrosis; histone deacetylase 1 (HDAC1); histone modification; transcription coactivator; transforming growth factor beta (TGF-B)