Vertebrate somitogenesis

In vertebrates, the paraxial mesoderm corresponds to the bilateral strips o f mesodermal tissue flanking the notochord and neural tube and which are de limited laterally by the intermediate mesoderm and the lateral plate. The p araxial mesoderm comprises the head or cephalic mesoderm anteriorly and the somitic region throughout the trunk and the tail of the vertebrates. Soon after gastrulation, the somitic region of vertebrates starts to become segm ented into paired blocks of mesoderm, termed somites. This process lasts un til the number of somites characteristic of the species is reached. The som ites later give rise to all skeletal muscles of the body, the axial skeleto n, and part of the dermis. In this review I discuss the processes involved in the formation of the paraxial mesoderm and its segmentation into somites in vertebrates.