The CXCR4/SDF-1 Axis in the Development of Facial Expression and Non-somitic Neck Muscles

Abstract

Trunk and head muscles originate from distinct embryonic regions: while the trunk muscles derive from the paraxial mesoderm that becomes segmented into somites, the majority of head muscles develops from the unsegmented cranial paraxial mesoderm. Differences in the molecular control of trunk versus head and neck muscles have been discovered about 25 years ago; interestingly, differences in satellite cell subpopulations were also described more recently. Specifically, the satellite cells of the facial expression muscles share properties with heart muscle. In adult vertebrates, neck muscles span the transition zone between head and trunk. Mastication and facial expression muscles derive from the mesodermal progenitor cells that are located in the first and second branchial arches, respectively. The cucullaris muscle (non-somitic neck muscle) originates from the posterior-most branchial arches. Like other subclasses within the chemokines and chemokine receptors, CXCR4 and SDF-1 play essential roles in the migration of cells within a number of various tissues during development. CXCR4 as receptor together with its ligand SDF-1 have mainly been described to regulate the migration of the trunk muscle progenitor cells. This review first underlines our recent understanding of the development of the facial expression (second arch-derived) muscles, focusing on new insights into the migration event and how this embryonic process is different from the development of mastication (first arch-derived) muscles. Other muscles associated with the head, such as non-somitic neck muscles derived from muscle progenitor cells located in the posterior branchial arches, are also in the focus of this review. Implications on human muscle dystrophies affecting the muscles of face and neck are also discussed.

The Emergence of Embryonic Myosin Heavy Chain during Branchiomeric Muscle Development

“…There are approximately 80 skeletal muscles in the human neck [ 39 ]. The mammalian neck consists of somite-derived muscle groups (epaxial and hypaxial) and non-somitic (branchiomeric muscles) muscles [ 3 , 14 , 27 , 28 , 39 ]. Skeletal muscle progenitor cells in the branchial arches 3–6 are thought to give rise to non-somitic neck muscles, for example, the trapezius muscle groups and sternocleidomastoideus muscle [ 14 , 39 ].…”

“…By now, it is widely accepted that branchiomeric and trunk muscles have different developmental histories [ 1 ]. Skeletal muscles in the trunk and limbs derive from somites (segmented paraxial mesoderm), whereas the majority of head muscle originates from the unsegmented cranial paraxial mesoderm [ 2 , 3 , 4 ]. Furthermore, head and trunk muscles have divergent genetic networks that control myogenesis [ 1 , 5 , 6 ].…”

New Insights into the Diversity of Branchiomeric Muscle Development: Genetic Programs and Differentiation

“…Although head muscles resemble limb and trunk muscles in myofiber architecture, their developmental history is widely divergent [ 11 ]. Branchiomeric muscles and their accompanying muscle stem cells develop from the cranial mesoderm (also known as pharyngeal mesoderm), which includes both the cranial paraxial mesoderm and lateral splanchnic mesoderm [ 1 , 25 , 26 , 27 , 28 ]. The pharyngeal mesoderm forms the mesodermal core within the pharyngeal arches (also known as branchial arches), which are transitory structures in the vertebrate embryo that bulge ventrally in pairs from the pharynx [ 1 , 5 ].…”

“…The mesodermal core of the pharyngeal arches gives rise to the branchiomeric muscles and significant parts of the heart [ 1 , 6 , 26 , 29 , 30 , 31 , 32 , 33 , 34 ]. The first and second pharyngeal arches give rise to masticatory and facial expression muscles, and posterior pharyngeal arches give rise to non-somitic neck muscles and esophagus striated muscles, respectively ( Figure 1 ) [ 1 , 6 , 25 , 26 , 28 , 31 , 35 ]. Moreover, a recent mouse genetic lineage analysis revealed that pharyngeal mesoderm contributes to the medial pharyngeal skeleton and branchiomeric muscle elements (connective tissue) [ 36 ].…”

Hoxa5 Activity Across the Lateral Somitic Frontier Regulates Development of the Mouse Sternum

“…Somites and LPM each give rise to skeletal tissue, including cartilage and bone, and to connective tissue such as tendons, ligaments, and muscle connective tissue (reviewed in ( Christ et al, 2007 ; Prummel et al, 2020 )). In contrast, all skeletal muscle is somite-derived, with the exception of some cranial muscles (reviewed in ( Yahya et al, 2020 )).…”