Temporally distinct transcriptional regulation of myocyte dedifferentiation and Myofiber growth during muscle regeneration

BMC Genomics

Research Article

Justin A. Colacino¹  Phillip E. Kish²  Alfonso Saera-Vila²  Ke’ale W. Louie³  Alon Kahana⁴ 

[1] Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, 48109, Ann Arbor, MI, USA;University of Michigan Comprehensive Cancer Center, 1500 E Medical Center Dr, 48109, Ann Arbor, MI, USA;Department of Nutritional Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, 48109, Ann Arbor, MI, USA;Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, 1000 Wall St, 48105, Ann Arbor, MI, USA;Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, 1000 Wall St, 48105, Ann Arbor, MI, USA;Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, 1011 N. University, 48109, Ann Arbor, MI, USA;Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, 1000 Wall St, 48105, Ann Arbor, MI, USA;University of Michigan Comprehensive Cancer Center, 1500 E Medical Center Dr, 48109, Ann Arbor, MI, USA;

关键词: Transcriptome;    RNA-sequencing;    Cell reprogramming;    Zebrafish;    Stem cell;    Polycomb;    Fibronectin;    Chromatin;    Epigenetic;   

DOI  :  10.1186/s12864-017-4236-y

 received in 2017-05-29, accepted in 2017-10-23,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundTissue regeneration requires a series of steps, beginning with generation of the necessary cell mass, followed by cell migration into damaged area, and ending with differentiation and integration with surrounding tissues. Temporal regulation of these steps lies at the heart of the regenerative process, yet its basis is not well understood. The ability of zebrafish to dedifferentiate mature “post-mitotic” myocytes into proliferating myoblasts that in turn regenerate lost muscle tissue provides an opportunity to probe the molecular mechanisms of regeneration.ResultsFollowing subtotal excision of adult zebrafish lateral rectus muscle, dedifferentiating residual myocytes were collected at two time points prior to cell cycle reentry and compared to uninjured muscles using RNA-seq. Functional annotation (GAGE or K-means clustering followed by GO enrichment) revealed a coordinated response encompassing epigenetic regulation of transcription, RNA processing, and DNA replication and repair, along with protein degradation and translation that would rewire the cellular proteome and metabolome. Selected candidate genes were phenotypically validated in vivo by morpholino knockdown. Rapidly induced gene products, such as the Polycomb group factors Ezh2 and Suz12a, were necessary for both efficient dedifferentiation (i.e. cell reprogramming leading to cell cycle reentry) and complete anatomic regeneration. In contrast, the late activated gene fibronectin was important for efficient anatomic muscle regeneration but not for the early step of myocyte cell cycle reentry.ConclusionsReprogramming of a “post-mitotic” myocyte into a dedifferentiated myoblast requires a complex coordinated effort that reshapes the cellular proteome and rewires metabolic pathways mediated by heritable yet nuanced epigenetic alterations and molecular switches, including transcription factors and non-coding RNAs. Our studies show that temporal regulation of gene expression is programmatically linked to distinct steps in the regeneration process, with immediate early expression driving dedifferentiation and reprogramming, and later expression facilitating anatomical regeneration.

【 授权许可】

CC BY   
© The Author(s). 2017