Location, Location, Location: Signals in Muscle Specification

Abstract

Muscles control body movement and locomotion, posture and body position and soft tissue support. Mesoderm derived cells gives rise to 700 unique muscles in humans as a result of well-orchestrated signaling and transcriptional networks in specific time and space. Although the anatomical structure of skeletal muscles is similar, their functions and locations are specialized. This is the result of specific signaling as the embryo grows and cells migrate to form different structures and organs. As cells progress to their next state, they suppress current sequence specific transcription factors (SSTF) and construct new networks to establish new myogenic features. In this review, we provide an overview of signaling pathways and gene regulatory networks during formation of the craniofacial, cardiac, vascular, trunk, and limb skeletal muscles.

Orofacial Muscles: Embryonic Development and Regeneration after Injury

“…The orofacial muscles comprise the muscles of the lower face and the oral cavity. Their development takes place in 2 different regions of the embryo head (Chang and Kioussi 2018). The mesoderm of the pharyngeal arches gives rise to the branchiomeric muscles that include the masticatory muscles, the buccinators, the orbicularis oris muscles, the muscles of the soft palate, and the suprahyoid muscles (Fig.…”

“…The occipital somites give rise to the muscles of the tongue (Fig. 1D) (Michailovici et al 2015;Chang and Kioussi 2018;Schubert et al 2018). Studies in chicks, rodents, and zebrafish show that cranial neural crest cells (CNCCs) in the embryo head direct muscle development and differentiate into the intramuscular connective tissue (Tzahor et al 2003;Grenier et al 2009;McGurk et al 2017).…”

“…The branchiomeric muscles ( Fig. 1) develop from the first, second, and fourth pharyngeal arches (Chang and Kioussi 2018). The third pharyngeal arch gives rise to the stylopharyngeous muscle, which is not considered an orofacial muscle (Frisdal and Trainor 2014).…”

“…The orofacial muscles include the muscles of mastication, the muscles of cheeks and lips, the soft palate muscles, the suprahyoid muscles, and the tongue muscles (Le Reverend et al 2014). These muscles develop from the mesoderm of the pharyngeal arches and the occipital somites (Sugii et al 2017;Chang and Kioussi 2018). The muscles of the trunk and limbs develop from the thoracic and lumbal somites, respectively (Chang and Kioussi 2018).…”

“…These muscles develop from the mesoderm of the pharyngeal arches and the occipital somites (Sugii et al 2017;Chang and Kioussi 2018). The muscles of the trunk and limbs develop from the thoracic and lumbal somites, respectively (Chang and Kioussi 2018). The molecular pathways that regulate orofacial muscle development differ from those in trunk and limb muscles (Chang and Kioussi 2018).…”