# Interkinetic nuclear migration in the zebrafish retina as a diffusive process

## TL;DR

This study uses advanced imaging techniques to model interkinetic nuclear migration in zebrafish retina as a diffusion process, revealing how nuclear packing influences migration dynamics and distribution during development.

## Contribution

It introduces a novel diffusive model of nuclear migration in the retina based on in vivo imaging data, linking physical processes to developmental behavior.

## Key findings

- Nuclear migration can be described as a diffusion process.
- Nuclear packing affects migration dynamics.
- The model explains nuclear distribution during retinogenesis.

## Abstract

A major hallmark of neural development is the oscillatory movement of nuclei between the apical and basal surfaces of the neuroepithelium during the process of interkinetic nuclear migration (IKNM). Here, we employ long-term, rapid lightsheet and two-photon imaging of zebrafish retinas $in~vivo$ during early development to uncover the physical processes that govern the behavior of nuclei during IKNM. These images allow the capture of reliable tracks of nuclear movements and division during early retinogenesis for many tightly packed nuclei. These tracks are then used to create and test a theory of retinal IKNM as a diffusive process across a nuclear concentration gradient generated by the addition of new nuclei at the apical surface. The analysis reveals the role of nuclear packing at the apical surface on the migration dynamics of nuclei, provides a robust quantitative explanation for the distribution of nuclei across the retina, and may have implications for stochastic fate choice in this system.