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bioRxiv · 10.1101/2024.04.28.590478

Sacrificing Adaptability for Functionality: The Ivory Tower of Macular Muller Cells

Abstract

The predilection of many retinal diseases for the macula suggests it may be less resistant to stress than the peripheral retina. Profiling of single-cell level transcriptional changes found that the peripheral retina exhibited more transcriptional changes than the macula in response to stress. One pronounced change was in a subgroup of Muller cells (MCs) that were dominant in the peripheral retina. Genes more abundantly expressed in peripheral MCs were mainly associated with stress responses and were more influenced by light stress. In contrast, genes highly expressed in MCs that predominated in the macula had roles in cellular function and were less influenced by light stress. Metallothionein 1, A Kinase Anchor Protein 12 and MAF BZIP Transcription Factor F were more abundantly expressed in peripheral MCs than in macular MCs. Knockdown of these genes in primary MCs reduced their viability under stress. Our findings indicate that macular MCs are more directed toward maintaining retinal function rather than mounting a stress response when exposed to stress, which may contribute to the maculas vulnerability to degenerative diseases.

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Zhang, T., Jin, K., Zeng, S., Yang, P., Zhu, M., Zhang, J., Chen, Y., Lee, S., Yam, M., Zeng, Y., Lu, X., Loo, L., Neely, G. G., Chang, A., Zhou, F., Du, J., Fan, X., Zhu, L., Gillies, M.. 2024-04-30. Sacrificing Adaptability for Functionality: The Ivory Tower of Macular Muller Cells. https://doi.org/10.1101/2024.04.28.590478

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