Identification and characterization of miRNA expression during zebrafish retinal regeneration

TL;DR: Dicer knockdown prior to light damage lead to decreased proliferation in regenerating retinas without affecting the number of Müller glia during retinal regeneration or cell death.

Abstract: by Rachel Harding Unlike most other vertebrates, zebrafish are able to regenerate many tissues including retina. Light-induced photoreceptor cell death causes inner nuclear layer Müller glia to dedifferentiate, reenter the cell cycle and produce proliferating progenitor cells. These progenitor cells continue to proliferate and migrate to the appropriate retinal layer and differentiate into functional photoreceptors. While a number of genes essential to retinal regeneration have been identified, the mechanisms regulating these genes have been little studied. Many post-transcriptional regulatory mechanisms exist in the cell including miRNAs, short RNA sequences encoded in the genome. To determine if miRNAs play a role in retinal regeneration, I reduced global miRNA expression by Dicer knockdown, an enzyme essential to miRNA maturation. Dicer knockdown prior to light damage lead to decreased proliferation in regenerating retinas without affecting the number of Müller glia during retinal regeneration or cell death. These studies demonstrate an essential role