Cell division and cadherin-mediated adhesion regulate lens epithelial cell movement in zebrafish

Abstract

In vertebrates, lens epithelial cells cover the anterior half of the lens fiber core. During development, lens epithelial cells proliferate, move posteriorly and differentiate into lens fiber cells after passing through the equator. To elucidate the mechanisms underlying lens epithelial cell movement, we conducted time-lapse imaging of zebrafish lens epithelium. Lens epithelial cells do not intermingle but maintain their relative positions during development. Cell division induces epithelial rearrangement, which subsequently promotes cell movement towards the equator. These data suggest that cell division is the major driving force for cell movement. In zebrafish, E-cadherin is expressed in lens epithelium, whereas N-cadherin is required for lens fiber growth. E-cadherin reduced lens epithelial cell movement, whereas N-cadherin enhanced it. Laser ablation experiments revealed that lens epithelium is governed by pulling tension, which is modulated by these cadherins. Thus, cell division and cadherinmediated adhesion regulate lens epithelial cell movement via modulation of epithelial tension.

Zebrafish Model in Ophthalmology to Study Disease Mechanism and Drug Discovery

“…After a series of morphogenetic events, the optic vesicle gives rise to the optic cup at 16 to 20 hpf, forms ventrally the optic fissure by 24 hpf, and later closes by 48 hpf [ 29 ]. The lens placode delaminates from the surface ectoderm cells overlying the optic cups at 16 hpf [ 6 , 30 ], forms a solid lens mass at approximately 24 hpf, and fully detaches from the surface ectoderm by the apoptosis of the intervening cells by 28 hpf [ 11 , 31 , 32 ]. At 30 hpf, the surface ectoderm that does not form the lens begins to possess corneal epithelial identity, and it forms migratory periocular mesenchymal cells migrating into the cornea from the peripheral regions of the optic cup between 30 and 36 hpf [ 7 , 33 ].…”

Mechanisms underlying microglial colonization of developing neural retina in zebrafish

“…Next, to evaluate the contribution of cell proliferation to the increasing number of ocular microglial precursors, we labeled ocular microglial precursors with markers of DNA replication. Here we used a zebrafish transgenic line, Tg[EF1α: mCherry-zGem] , which specifically marks proliferative cells in S and G2 phases (Mochizuki et al, 2017; Mochizuki et al, 2014). We combined this Tg[EF1α: mCherry-zGem] system with Tg[mpeg1 .…”