title: Characterisation and expression of myogenesis regulatory factors during in vitro myoblast development and in vivo fasting in the gilthead sea bream (Sparus aurata).
abstract: The aim of this study was to characterise a primary cell culture isolated from fast skeletal muscle of the gilthead sea bream. Gene expression profiles during culture maturation were compared with those obtained from a fasting-refeeding model which is widely used to modulate myogenesis in vivo. Myogenesis is controlled by numerous extracellular signals together with intracellular transcriptional factors whose coordinated expression is critical for the appropriate development of muscle fibres. Full-length cDNAs for the transcription factors Myf5, Mrf4, Pax7 and Sox8 were cloned and sequenced for gilthead sea bream. Pax7, sox8, myod2 and myf5 levels were up-regulated during the proliferating phase of the myogenic cultures coincident with the highest expression of proliferating cell nuclear antigen (PCNA). In contrast, myogenin and mrf4 transcript abundance was highest during the differentiation phase of the culture when myotubes were present, and was correlated with increased myosin heavy chain (mhc) and desmin expression. In vivo, 30days of fasting resulted in muscle fibre atrophy, a reduction in myod2, myf5 and igf1 expression, lower number of Myod-positive cells, and decreased PCNA protein expression, whereas myogenin expression was not significantly affected. Myostatin1 (mstn1) and pax7 expression were up-regulated in fasted relative to well-fed individuals, consistent with a role for Pax7 in the reduction of myogenic cell activity with fasting. The primary cell cultures and fasting-feeding experiments described provide a foundation for the future investigations on the regulation of muscle growth in gilthead sea bream.
authors.affiliation: Departament de Fisiologia i Immunologia, Facultat de Biologia, Barcelona Knowledge Campus, Universitat de Barcelona, 08028, Barcelona, Spain; Scottish Oceans Institute, School of Biology, University of St Andrews, Fife KY16 8LB, St Andrews, Scotland, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: García de la serrana
authors.forename: Marta
authors.initials: M
authors.lastname: Codina
authors.forename: Encarnación
authors.initials: E
authors.lastname: Capilla
authors.forename: Vanesa
authors.initials: V
authors.lastname: Jiménez-Amilburu
authors.forename: Isabel
authors.initials: I
authors.lastname: Navarro
authors.forename: Shao-Jun
authors.initials: SJ
authors.lastname: Du
authors.forename: Ian A
authors.initials: IA
authors.lastname: Johnston
authors.forename: Joaquim
authors.initials: J
authors.lastname: Gutiérrez
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003893:Desmin / Q000235:genetics / Q000378:metabolism; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D005508:Food Deprivation; D024510:Muscle Development; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism; D032446:Myoblasts / Q000502:physiology*; D018006:Myogenic Regulatory Factors / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D051763:PAX7 Transcription Factor / Q000235:genetics / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D055757:SOXE Transcription Factors / Q000235:genetics / Q000378:metabolism; D021541:Sea Bream / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D013002:Somatomedins / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome
chemical_list: D003893:Desmin; D029941:Fish Proteins; D018006:Myogenic Regulatory Factors; D051763:PAX7 Transcription Factor; D018809:Proliferating Cell Nuclear Antigen; D055757:SOXE Transcription Factors; D013002:Somatomedins
keywords: Mrf4; Myf5; Myod; Myogenesis; Myogenin; Pax7; Primary cell cultures; Sox8