Symmetry and fluctuation of cell movements in neural crest-derived facial mesenchyme

Abstract

In the face, symmetry is established when bilateral streams of neural crest cells leave the neural tube at the same time, follow identical migration routes and then give rise to the facial prominences. However developmental instability exists, particularly surrounding the steps of lip fusion. The causes of instability are unknown but inability to cope with developmental fluctuations are a likely cause of congenital malformations such as non-syndromic orofacial clefts. Here, we tracked cell movements over time in the frontonasal mass which forms the facial midline and participates in lip fusion using live-cell imaging. Our mathematical examination of cell velocity vectors uncovered temporal fluctuations in several parameters including order/disorder, symmetry/asymmetry and divergence/convergence. We found that treatment with a RhoGTPase inhibitor completely disrupted the temporal fluctuations in all measures and blocked morphogenesis. Thus we discovered that genetic control of symmetry extends to mesenchymal cell movements and that these movements are of the type that could be perturbed in in asymmetrical malformations such as non-syndromic cleft lip.

High throughput miRNA sequencing and bioinformatics analysis identify the mesenchymal cell proliferation and apoptosis related miRNAs during fetal mice palate development

“…4 Inhibition of the proliferation and migration of palatal mesenchymal cells leads to the short development of palatal processes and the failure of palatal processes to connect, resulting in the formation of cleft palate. 5 Moreover, the degeneration or apoptosis of crest epithelial cells in the palatal process, and the inhibition of epithelial-mesenchymal transition (EMT) can also lead to the fusion obstacle of palatal process and the formation of cleft palate. Recent studies reported that microRNAs (miRNAs) are key factors in both normal palatogenesis and cleft palate formation.…”

Evaluation of Mandibular Growth and Symmetry in Child with Congenital Zygomatic-Coronoid Ankylosis

“…This fact is explained, among other things, by a dominant growth potential of the skull and brain on the right side of the face or a greater expression of emotions on the left side of the face [8]. It has been also speculated that neural crest cell migration during fetal growth happens earlier on the right side and tends to be delayed on the left side [9,10].…”

“…This fact is explained, among other things, by a dominant growth potential of skull and brain on the right side of the face or a greater expression of emotions on the side of the face [8]. It has been also speculated that neural crest cell migration during fe growth happens earlier on the right side and tends to be delayed on the left side [9,10] (a) (b) Despite the dominance of genetic factors, the mandible's development is sensitive to the influence of modifying en ronmental factors [11,12], such as diet, functioning/loads exerted on the stomatognathic system, size and type of o Despite the dominance of genetic factors, the mandible's development is sensitive to the influence of modifying environmental factors [11,12], such as diet, functioning/loads exerted on the stomatognathic system, size and type of occlusion, work of muscles and muscular tone (including masseter muscles, suprahyoid and infrahyoid muscles, temporal and pterygoid muscles). The most significant factors modifying the development of the stomatognathic system are pathological conditions and dysfunctions of the masticatory organ.…”

“…This fact is explained, among other things, by a dominant growth potential of the skull and brain on the right side of the face or a greater expression of emotions on the left side of the face [8]. It has been also speculated that neural crest cell migration during fetal growth happens earlier on the right side and tends to be delayed on the left side [9,10]. Despite the dominance of genetic factors, the mandible's development is sensitive to the influence of modifying environmental factors [11,12], such as diet, functioning/loads exerted on the stomatognathic system, size and type of oc- In addition, four angles were measured (Figure 6):…”

The people behind the papers – Adrian Danescu, Lisanne Rens and Joy Richman

“…LR: For me, luckily not as many frustrations as with other projects I've done! I think the biggest challenge was how to interpret what Composite figure of the key experimental data in the paper; for more details, see the full manuscript (Danescu et al, 2021).…”