Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Genome-wide analysis of murine cardiomyocytes at different developmental stages

ABSTRACT: Cardiomyocytes exhibit differential growth patterns throughout development. In fetal life the increase in cardiac mass is associated with hyperplastic growth and cardiomyocyte proliferation. The majority of fetal cardiomyocytes are also mononucleated. During the early neonatal period in mice there is a switch from hyperplastic to hypertrophic growth of cardiomyocytes. This period is characterized by bi-nucleation and polyploidization of cardiomyocyte nuclei and a decreased capacity for cardiomyocytes to proliferate and complete cytokinesis. Increases in myocardial mass occur predominantly via hypertrophic growth. Adult mammalian cardiomyocytes are generally accepted to have little or no proliferative capacity and to be terminally withdrawn from the cell cycle. The vast majority of adult murine cardiomyocytes are bi-nucleated. The present study sought to accurately establish the growth pattern of cardiomyocytes throughout development in mice and identify genes associated with the switch from hyperplastic to hypertrophic growth. These cell cycle associated genes are crucial to the understanding of the mechanisms of bi-nucleation, polyploidization and hypertrophy in the neonatal period. Cardiomyocytes were FACS sorted from the hearts of ED11-12 embryos, neonatal day 3-4 and adult (10 week) eGFP ?-MHC mice whereby GFP expression is driven constitutively by the ?-MHC promoter. Gene analyses identified genes whose expression was predicted to be particular to day 3 -4 neonatal cardiomyocytes, compared to embryonic or adult cells. Cell cycle associated genes are crucial to the understanding of the mechanisms of bi-nucleation and hypertrophy in the neonatal period, and offer attractive candidates for manipulation. Total RNA obtained from isolated cardiomyocytes from ED11-12; Neonatal day 3-4 and adult timepoints compared with each other. Several hearts per sample, RNA was pooled within samples. FACS samples were prepared in the following manner: embryonic, neonatal and adult hearts were dissected and dissociated to single cell solution with Liberase Blendzyme 3 (0.1 mg/ml) (Roche Diagnostics), washed and spun down and resuspended in cardiomyocyte isolation buffer (130 mM NaCl; 5 mM KCl; 1.2 mM KH2PO4; 6 mM HEPES; 5 mM NaHCO3; 1 mM MgCl2; 5 mM Glucose).

ORGANISM(S): Mus musculus

SUBMITTER: Annica PontÃ©n

PROVIDER: E-GEOD-17020 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Cardiomyocyte cell cycle control and growth estimation in vivo--an analysis based on cardiomyocyte nuclei.

Walsh Stuart S Pontén Annica A Fleischmann Bernd K BK Jovinge Stefan S

Cardiovascular research 20100113 3

<h4>Aims</h4>Adult mammalian cardiomyocytes are traditionally viewed as being permanently withdrawn from the cell cycle. Whereas some groups have reported none, others have reported extensive mitosis in adult myocardium under steady-state conditions. Recently, a highly specific assay of 14C dating in humans has suggested a continuous generation of cardiomyocytes in the adult, albeit at a very low rate. Mice represent the most commonly used animal model for these studies, but their short lifespan ...[more]

PMID: 20071355

Similar Datasets

Project description:Background: Discovering determinants of cardiomyocyte maturity will be critical to understanding the maintenance of differentiated states and potentially reawakening endogenous regenerative programs in adult mammalian hearts as a therapeutic strategy. Recent evidence has suggested that forced dedifferentiation paired with oncogene expression is sufficient to drive cardiac regeneration. However, elucidation of endogenous developmental determinants of the switch between regenerative and mature cardiomyocyte cell states is necessary for optimal design of regenerative approaches for heart disease. Muscleblind-like 1 (MBNL1) regulates both fibroblast and erythroid differentiation and proliferation. Hence, we examined whether MBNL1 promotes and maintains mature cardiomyocyte states while antagonizing cardiomyocyte proliferation. Methods: MBNL1 gain- and loss-of-function mouse models were studied at several developmental timepoints and in surgical models of heart regeneration. Multi-omics approaches were combined with biochemical, histological, and in vitro genetic work to determine the mechanisms through which MBNL1 exerts its effects. Results: MBNL1 is co-expressed with a maturation-association genetic program in the heart and is regulated by the MEIS1/Calcineurin signaling axis. Targeted MBNL1 overexpression early in development prematurely transitioned cardiomyocytes to hypertrophic growth, hypoplasia, and dysfunction, while loss of MBNL1 function increased cardiomyocyte cell cycle entry and proliferation through altered cell cycle inhibitor transcript stability. Moreover, MBNL1-dependent stabilization of estrogen-related receptor signaling was essential for maintaining cardiomyocyte maturity in adult myocytes. In accordance with these data, modulating MBNL1 dose tuned the temporal window of neonatal cardiac regeneration, where increased MBNL1 expression arrested myocyte proliferation and regeneration, and MBNL1 deletion promoted regenerative states with prolonged myocyte proliferation. However, MBNL1 deletion was not sufficient to promote regeneration in the adult heart due to cell-cycle checkpoint activation. Conclusions: Here, MBNL1 was identified as an essential regulator of cardiomyocyte differentiated states, their developmental switch from hyperplastic to hypertrophic growth, and their regenerative potential through controlling an entire maturation program by stabilizing adult myocyte mRNAs during postnatal development and throughout adulthood. Additionally, MBNL1-dependent perturbations of a myocyte’s preferred growth mechanism at a given developmental state had detrimental consequences to cardiac function, and targeting loss of maturity and removing cell cycle inhibitors was not insufficient to promote adult regeneration.

Dataset Information

Genome-wide analysis of murine cardiomyocytes at different developmental stages

Publications

Cardiomyocyte cell cycle control and growth estimation in vivo--an analysis based on cardiomyocyte nuclei.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets