Washington, Feb 1 : US researchers have identified a gene that is the key switch that allows embryonic cells to form into muscles in zebrafish.
According to Monte Westerfield, a professor of biology and researcher in the University of Oregon Institute of Neuroscience, the trigger gene, which is identified as Smarcd3, must align correctly with two other genes for muscle formation to begin, a process known as myogenesis.
Smarcd3 proteins are part of a chromatin-remodelling complex made up of DNA and proteins that make up chromosomes. It is a transcriptional protein, which means it is important for initiating, in this case, development.
In the study, the researchers used zebrafish embryos, which provide a model system for analysing the genetic control of induction and specification of muscle cells in vertebrates, as well as for many other important health issues.
"Our muscles develop from a particular set of cells in the embryo. These muscle precursor cells need to be in the right place at the right time to develop into muscles. Previously it was unknown how the timing of this critical developmental switch is controlled. We discovered the missing factor, Smarcd3, which forms a protein complex that alters the shape of DNA in particular regions of the genome, thus turning on genes required for cells to develop into muscle," Westerfield said.
The researchers found that muscle formation begins in an embryo's mesoderm when Smarcd3 interacts correctly with two other transcription-factors known as Fgf and Ntl.
The researchers noted that this specific time-sensitive alignment, works to trigger the earliest gene expression involved in myogenesis.
The findings could eventually allow researchers to understand how various combinations of proteins in the chromatin act to regulate the development of different cell types, tissues and organs.
The study is published is the Journal of Biological Chemistry.