Evolutionary history and epigenetic regulation of the three paralogous pax7 genes in rainbow trout
- 417 Downloads
The extraordinary muscle growth potential of teleost fish, particular those of the Salmoninae clade, elicits questions about the regulation of the relatively highly conserved transcription factors of the myogenic program. The pseudotetraploid nature of the salmonid genome adds another layer of regulatory complexity that must be reconciled with epigenetic data to improve our understanding of the achievement of lifelong muscle growth in these fish. We identify three paralogous pax7 genes (pax7a1, pax7a2 and pax7b) in the rainbow trout genome. During in vitro myogenesis, pax7a1 transcripts remain stable, whereas pax7a2 and pax7b mRNAs increase in abundance, similarly to myogenin mRNAs but in contrast to the expression pattern of the mammalian ortholog. We also profile the distribution of repressive H3K27me3 and H3K9me3 and permissive H3K4me3 marks during in vitro myogenesis across these loci and find that pax7a2 expression is associated with decreased H3K27 trimethylation, whereas pax7b expression is correlated with decreased H3K9me3 and H3K27me3. These data link the unique differential expression of pax7 paralogs with epigenetic histone modifications in a vertebrate species displaying growth divergent from that of mammals and highlight an important divergence in the regulatory mechanisms of pax7 expression among vertebrates. The system described here provides a more comprehensive picture of the combinatorial control mechanisms orchestrating skeletal muscle growth in a salmonid, leading to a better understanding of myogenesis in this species and across Vertebrata more generally.
Keywordspax7 Epigenetic regulation Histone methylation ChIP Rainbow trout
The authors thank Ikram Belghit, Imad Aharchaou and Alexandre Herman for their assistance in the setting up of the initial rainbow trout primary myoblast cultures.
- Berthelot C, Brunet F, Chalopin D, Juanchich A, Bernard M, Noel B, Bento P, Da Silva C, Labadie K, Alberti A, Aury JM, Louis A, Dehais P, Bardou P, Montfort J, Klopp C, Cabau C, Gaspin C, Thorgaard GH, Boussaha M, Quillet E, Guyomard R, Galiana D, Bobe J, Volff JN, Genet C, Wincker P, Jaillon O, Roest Crollius H, Guiguen Y (2014) The rainbow trout genome provides novel insights into evolution after whole-genome duplication in vertebrates. Nat Commun 5:3657CrossRefPubMedCentralPubMedGoogle Scholar
- Froehlich JM, Seiliez I, Gabillard JC, Biga PR (2014) Preparation of primary myogenic precursor cell/myoblast cultures from basal vertebrate lineages. J Vis Exp 86:(in press)Google Scholar
- Halevy O, Piestun Y, Allouh MZ, Rosser BW, Rinkevich Y, Reshef R, Rozenboim I, Wleklinski-Lee M, Yablonka-Reuveni Z (2004) Pattern of Pax7 expression during myogenesis in the posthatch chicken establishes a model for satellite cell differentiation and renewal. Dev Dyn 231:489–502CrossRefPubMedGoogle Scholar
- Jaillon O, Aury JM, Brunet F, Petit JL, Stange-Thomann N, Mauceli E, Bouneau L, Fischer C, Ozouf-Costaz C, Bernot A, Nicaud S, Jaffe D, Fisher S, Lutfalla G, Dossat C, Segurens B, Dasilva C, Salanoubat M, Levy M, Boudet N, Castellano S, Anthouard V, Jubin C, Castelli V, Katinka M, Vacherie B, Biemont C, Skalli Z, Cattolico L, Poulain J, De Berardinis V, Cruaud C, Duprat S, Brottier P, Coutanceau JP, Gouzy J, Parra G, Lardier G, Chapple C, McKernan KJ, McEwan P, Bosak S, Kellis M, Volff JN, Guigo R, Zody MC, Mesirov J, Lindblad-Toh K, Birren B, Nusbaum C, Kahn D, Robinson-Rechavi M, Laudet V, Schachter V, Quetier F, Saurin W, Scarpelli C, Wincker P, Lander ES, Weissenbach J, Roest Crollius H (2004) Genome duplication in the teleost fish Tetraodon nigroviridis reveals the early vertebrate proto-karyotype. Nature 431:946–957CrossRefPubMedGoogle Scholar
- Krogan NJ, Dover J, Wood A, Schneider J, Heidt J, Boateng MA, Dean K, Ryan OW, Golshani A, Johnston M, Greenblatt JF, Shilatifard A (2003a) The Paf1 complex is required for histone H3 methylation by COMPASS and Dot1p: linking transcriptional elongation to histone methylation. Mol Cell 11:721–729CrossRefPubMedGoogle Scholar
- Krogan NJ, Kim M, Tong A, Golshani A, Cagney G, Canadien V, Richards DP, Beattie BK, Emili A, Boone C, Shilatifard A, Buratowski S, Greenblatt J (2003b) Methylation of histone H3 by Set2 in Saccharomyces cerevisiae is linked to transcriptional elongation by RNA polymerase II. Mol Cell Biol 23:4207–4218CrossRefPubMedCentralPubMedGoogle Scholar
- Palacios D, Mozzetta C, Consalvi S, Caretti G, Saccone V, Proserpio V, Marquez VE, Valente S, Mai A, Forcales SV, Sartorelli V, Puri PL (2010) TNF/p38alpha/polycomb signaling to Pax7 locus in satellite cells links inflammation to the epigenetic control of muscle regeneration. Cell Stem Cell 7:455–469CrossRefPubMedCentralPubMedGoogle Scholar
- Schultz DC, Ayyanathan K, Negorev D, Maul GG, Rauscher FJ 3rd (2002) SETDB1: a novel KAP-1-associated histone H3, lysine 9-specific methyltransferase that contributes to HP1-mediated silencing of euchromatic genes by KRAB zinc-finger proteins. Genes Dev 16:919–932CrossRefPubMedCentralPubMedGoogle Scholar
- Sebastian S, Sreenivas P, Sambasivan R, Cheedipudi S, Kandalla P, Pavlath GK, Dhawan J (2009) MLL5, a trithorax homolog, indirectly regulates H3K4 methylation, represses cyclin A2 expression, and promotes myogenic differentiation. Proc Natl Acad Sci U S A 106:4719–4724CrossRefPubMedCentralPubMedGoogle Scholar
- Stojic L, Jasencakova Z, Prezioso C, Stutzer A, Bodega B, Pasini D, Klingberg R, Mozzetta C, Margueron R, Puri PL, Schwarzer D, Helin K, Fischle W, Orlando V (2011) Chromatin regulated interchange between polycomb repressive complex 2 (PRC2)-Ezh2 and PRC2-Ezh1 complexes controls myogenin activation in skeletal muscle cells. Epigenetics Chromatin 4:16CrossRefPubMedCentralPubMedGoogle Scholar
- Yamane H, Nishikawa A (2013) Differential muscle regulatory factor gene expression between larval and adult myogenesis in the frog Xenopus laevis: adult myogenic cell-specific myf5 upregulation and its relation to the notochord suppression of adult muscle differentiation. Vitro Cell Dev Biol Anim 49:524–536CrossRefGoogle Scholar