The vertebrate Embryo Clock: Common players dancing to a different beat.

Vertebrate embryo somitogenesis is the earliest morphological manifestation of the characteristic patterned structure of the adult axial skeleton. Pairs of somites flanking the neural tube are formed periodically during early development, and the molecular mechanisms in temporal control of this early patterning event have been thoroughly studied. The discovery of a molecular Embryo Clock (EC) underlying the periodicity of somite formation shed light on the importance of gene expression dynamics for pattern formation.

gga-miRNOME, a microRNA-sequencing dataset from chick embryonic tissues.

MicroRNAs (miRNAs) are small non-coding RNA molecules, with sizes ranging from 18 to 25 nucleotides, which are key players in gene expression regulation. These molecules play an important role in fine-tuning early vertebrate embryo development. However, there are scarce publicly available miRNA datasets from non-mammal embryos, such as the chicken (Gallus gallus), which is a classical model system to study vertebrate embryogenesis.

MicroRNA processing machinery in the developing chick embryo.

Gene expression regulation during embryo development is under strict regulation to ensure proper gene expression in both time and space. The involvement of microRNAs (miRNA) in early vertebrate development is documented and inactivation of different proteins involved in miRNA synthesis results in severe malformations or even arrests vertebrate embryo development. However, there is very limited information on when and in what tissues the genes encoding these proteins are expressed.