Characterization of Early Cardiac-Specific Transcripts in Embryonic Stem Cell-Derived Progenitors - A Transcriptional Profiling

• Published in: Tissue engineering. Part A 2009-03, Vol.15 (3), p.687-687
• Main Authors: Rolletschek, A, Schmitteckert, S, Schulz, H, Huebner, N, Wobus, A M, Weibezahn, K-F
• Format: Article
• Language: English
• ISSN: 1937-3341; 1937-335X

During in vitro differentiation, embryonic stem (ES) cells recapitulate cellular developmental processes and gene expression patterns of early embryogenesis. Here, we characterize early stages of cardiac differentiation of mouse ES cells. ES cells were cultured as embryoid bodies (EBs) for 5 days (d). After plating EBs were spontaneously differentiated for 9d into a multilineage progenitor population representing cells of all three primary germ layers including early cardiomyocytes. To investigate this stage of multi-lineage progenitors and of early cardiac cell types at the transcript level, microarray analysis was performed using Affymetrix chips comparing undifferentiated ES cells and 5 + 9d progenitors followed by RT-PCR analysis. Transcript levels of transcriptional regulators (e.g. Tbx20, GATA4, Pitx2), extra-cellular matrix components (e.g. procollagens I, III, IV, MMPs), and cytoskeletal proteins (troponins T2 and C, cardiac alpha actin) involved in cardiac differentiation and function were found to be up regulated. Specifically, we detected a subset of up regulated transcripts of genes known to be expressed in the cardiac neural crest or its derivatives. mRNA levels of transcription factors Hand1 and Hand2, known to control cardiomyocyte-specific gene expression through interaction with other transcription factors, and the neural crest-specific genes Mef2c, Id2, Lbx1, Efnb1, and Sema3c were clearly up regulated at this early stage of cardiogenesis. Also, the presence of the neural crest marker, Mab 4E9R in this population suggests the involvement of neural crest-specific genes and proteins at an early stage of cardiac differentiation. Immuno-cytochemistry is presently performed to analyse the potential role of cardiac neural crest cells in early ES-derived cardiogenesis.