Dataset Information

Dynamic miRNA expression patterns during retinal regeneration in zebrafish: reduced dicer or miRNA expression suppresses proliferation of Muller glia-derived neuronal progenitor cells.

ABSTRACT:

Background

Adult zebrafish spontaneously regenerate their retinas after damage. Although a number of genes and signaling pathways involved in regeneration have been identified, the exact mechanisms regulating various aspects of regeneration are unclear. microRNAs (miRNAs) were examined for their potential roles in regulating zebrafish retinal regeneration.

Results

To investigate the requirement of miRNAs during zebrafish retinal regeneration, we knocked down the expression of Dicer in retinas prior to light-induced damage. Reduced Dicer expression significantly decreased the number of proliferating Müller glia-derived neuronal progenitor cells during regeneration. To identify individual miRNAs with roles in neuronal progenitor cell proliferation, we collected retinas at different stages of light damage and performed small RNA high-throughput sequencing. We identified subsets of miRNAs that were differentially expressed during active regeneration but returned to basal levels once regeneration was completed. We then knocked down five different miRNAs that increased in expression and assessed the effects on retinal regeneration. Reduction of miR-142b and miR-146a expression significantly reduced INL proliferation at 51 h of light treatment, while knockdown of miR-7a, miR-27c, and miR-31 expression significantly reduced INL proliferation at 72 h of constant light.

Conclusions

miRNAs exhibit dynamic expression profiles during retinal regeneration and are necessary for neuronal progenitor cell proliferation.

SUBMITTER: Rajaram K

PROVIDER: S-EPMC4237695 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Publications

Dynamic miRNA expression patterns during retinal regeneration in zebrafish: reduced dicer or miRNA expression suppresses proliferation of Müller glia-derived neuronal progenitor cells.

Rajaram Kamya K Harding Rachel L RL Bailey Travis T Patton James G JG Hyde David R DR

Developmental dynamics : an official publication of the American Association of Anatomists 20141010 12

<h4>Background</h4>Adult zebrafish spontaneously regenerate their retinas after damage. Although a number of genes and signaling pathways involved in regeneration have been identified, the exact mechanisms regulating various aspects of regeneration are unclear. microRNAs (miRNAs) were examined for their potential roles in regulating zebrafish retinal regeneration.<h4>Results</h4>To investigate the requirement of miRNAs during zebrafish retinal regeneration, we knocked down the expression of Dice ...[more]

PMID: 25220904

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