Abstract
Understanding the mechanisms of early cardiac fate determination may lead to better approaches in promoting heart regeneration. We used a mesoderm posterior 1 (Mesp1)-Cre/Rosa26-EYFP reporter system to identify microRNAs (miRNAs) enriched in early cardiac progenitor cells. Most of these miRNA genes bear MESP1-binding sites and active histone signatures. In a calcium transient-based screening assay, we identified miRNAs that may promote the cardiomyocyte program. An X-chromosome miRNA cluster, miR-322/-503, is the most enriched in the Mesp1 lineage and is the most potent in the screening assay. It is specifically expressed in the looping heart. Ectopic miR-322/-503 mimicking the endogenous temporal patterns specifically drives a cardiomyocyte program while inhibiting neural lineages, likely by targeting the RNA-binding protein CUG-binding protein Elav-like family member 1 (Celf1). Thus, early miRNAs in lineage-committed cells may play powerful roles in cell-fate determination by cross-suppressing other lineages. miRNAs identified in this study, especially miR-322/-503, are potent regulators of early cardiac fate.
Keywords:
cardiomyocyte; miR-322; miR-424; miR-503; microRNA.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
Bacterial Proteins / genetics
-
Bacterial Proteins / metabolism
-
Basic Helix-Loop-Helix Transcription Factors / genetics*
-
Basic Helix-Loop-Helix Transcription Factors / metabolism
-
CELF1 Protein / genetics
-
CELF1 Protein / metabolism
-
Cell Differentiation
-
Cell Lineage / genetics
-
Embryo, Mammalian
-
Gene Expression Profiling
-
Gene Expression Regulation, Developmental*
-
Genes, Reporter
-
Integrases / genetics
-
Integrases / metabolism
-
Luminescent Proteins / genetics
-
Luminescent Proteins / metabolism
-
Mesoderm / cytology
-
Mesoderm / growth & development
-
Mesoderm / metabolism
-
Mice
-
Mice, Transgenic
-
MicroRNAs / genetics*
-
MicroRNAs / metabolism
-
Morphogenesis / genetics
-
Mouse Embryonic Stem Cells / cytology
-
Mouse Embryonic Stem Cells / metabolism*
-
Myocytes, Cardiac / cytology
-
Myocytes, Cardiac / metabolism*
-
Primary Cell Culture
-
RNA, Untranslated / genetics
-
RNA, Untranslated / metabolism
-
Signal Transduction
Substances
-
Bacterial Proteins
-
Basic Helix-Loop-Helix Transcription Factors
-
CELF1 Protein
-
CELF1 protein, mouse
-
Gt(ROSA)26Sor non-coding RNA, mouse
-
Luminescent Proteins
-
MIRN322 microRNA, mouse
-
Mesp1 protein, mouse
-
MicroRNAs
-
Mirn503 microRNA, mouse
-
RNA, Untranslated
-
yellow fluorescent protein, Bacteria
-
Cre recombinase
-
Integrases