Abstract: PO0632
The Regenerative Response to Renal Injury of the African Spiny Mouse Is Epigenetically Regulated Through H3K27 Methylation
Session Information
- Development, Stem Cells, and Regenerative Medicine
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Development, Stem Cells, and Regenerative Medicine
- 500 Development, Stem Cells, and Regenerative Medicine
Authors
- Nguyen, Elizabeth D., Seattle Children's Research Institute, Seattle, Washington, United States
- Okamura, Daryl M., Seattle Children's Research Institute, Seattle, Washington, United States
- Houghtaling, Scott Robert, Seattle Children's Research Institute, Seattle, Washington, United States
- Collins, Sarah J., Seattle Children's Research Institute, Seattle, Washington, United States
- Timms, Andrew E., Seattle Children's Research Institute, Seattle, Washington, United States
- Beier, David R., Seattle Children's Research Institute, Seattle, Washington, United States
- Majesky, Mark W., Seattle Children's Research Institute, Seattle, Washington, United States
Background
Lysine methylation of histones plays an important role in regulating gene expression. When tri-methylated, chromatin regions marked by H3K27me3 are inaccessible for transcription. EZH2 of the Polycomb group methylates H3K27, with opposing action carried out by histone demethylases JMJD3 & UTX. EZH2 activation and subsequent increase in H3K27me3 has been associated with renal fibrosis. We hypothesize that in the African spiny mouse, a mammalian model of kidney regeneration, demethylation of H3K27 is associated with regenerative wound healing after ischemia-reperfusion kidney injury.
Methods
Experiments were carried out on kidneys of spiny mouse and house mouse in normal kidneys and kidneys 1 & 3 days after unilateral ischemia-reperfusion injury. Mass spectrometry was used to profile histone modifications. Expression of key genes involved in methylation of H3K27 were quantified using RNA-sequencing, and protein concentration was quantified by western blot. H3K27me3 marks were visualized by immunofluorescent staining. Genes marked by H3K27me3 were identified using CUT&RUN ChIP-sequencing.
Results
H3K27me3 is significantly increased in mouse kidney after ischemia reperfusion injury whereas no change in the repressive mark was noted in spiny mouse when quantified by mass spectrometry and western blot. H3K27me3 marks are abundant in fibrotic mouse kidneys and distributed throughout kidney tissue, while H3K27me3 is reduced in repaired kidneys of spiny mouse. RNA-sequencing demonstrated a 4-fold increase in Ezh2 in mouse after injury vs 2-fold increase in spiny mouse. During the course of injury, Jmjd3 expression increased in spiny mouse but decreased in expression in mouse. We previously identified nephrogenic progenitor genes potentially associated with regenerative wound healing in spiny mouse, including Cdh1, Cdh6 and H19. CUT&RUN identified these genes as repressively marked by H3K27me3 in mouse but available for transcription in spiny mouse.
Conclusion
This work suggests that the regenerative response to renal injury in spiny mouse is orchestrated at least in part through the methylation of histone H3K27. Modification of the histone methylation landscape through small molecular modulators may redirect the outcome of kidney injury from fibrosis to regeneration.
Funding
- NIDDK Support