Under the influence of vertically oriented 
microtubules, cells of the developing neural plate elongate, while 
contraction of actin microfilaments arranged circumferentially 
around the apical portions of the cells results in cells with a broad base and narrow apex.The 
process of neural fold bending in a dorsomedial direction also 
appears to involve differential proliferation and translocation 
of the neuroepithelial cells.34 Surface glycoproteins, especially 
cell adhesion molecules important for cell-cell recognition, as 
well as adhesive interactions with extracellular matrix, mediate 
fusion of the opposing neural folds.1.1).