In a new study that makes the cover of the January issue of Cell Reports, researchers led by Pr. Cédric Blanpain, WELBIO investigator at ULB uncovered the number and mode of growth of the earliest cardiac progenitors during mouse heart morphogenesis.
The heart is a complex organ that contains four different chambers and different cell types. It is the first organ formed during embryogenesis. During development, it is crucial that a precise number of cardiac progenitors are specified at the correct time, migrate at the correct place and proliferate to expand the pool of progenitors and ensure the harmonious morphogenesis and growth of the heart. Any defects during this critical stage of development will lead to congenital heart diseases, which represent the first cause of severe birth malformations.
Samira Chabab and colleagues performed a mosaic and a temporal clonal analysis of early cardiac progenitors combined with quantitative biophysical analysis to investigate their mode of growth during embryonic development. Using a multidisciplinary approach, they found that about 250 cardiac progenitors contribute to heart formation. « It will be very interesting to assess whether these progenitors are plastic and what is the consequence of changing the number of progenitors to the harmonious heart development. » comments Samira Chabab, the first author of this study.
In addition, the shape of the progeny of single cardiac progenitors revealed that depending of the heart regions the progenitors growth differentially. Surprisingly, they found that despite their emergence at different time points during embryonic development and their differential contribution to different heart regions, the different subpopulation of cardiac progenitors share remarkably similar proliferative behaviour.
In conclusion, this work provides new insights into the number and mode of growth of cardiac progenitors during mammalian development that have important implications for understanding the mechanisms underlying congenital heart defects and other organ malformations. « This approach can now be used to understand the number of progenitors and growth of different tissues and organs, which may have important implications for understanding congenital malformations» comments Cédric Blanpain, the senior author of this study.
Chabab et al, Uncovering the number and clonal dynamics of Mesp1 progenitors during heart morphogenesis, Cell Reports (2016) 4 : 1-10