Maea, also known as macrophage erythroblast attacher or EMP, is an E3 ubiquitin ligase. It is involved in multiple biological processes such as canonical Wnt signalling, cytokine receptor regulation, and ubiquitin-proteasome system-mediated protein degradation. It plays a crucial role in early embryogenesis, haematopoietic stem cell maintenance, and erythropoiesis [2,3,4]. Genetic models like KO/CKO mouse models are valuable in studying its functions.

In Maea-deficient mice, deletion in macrophages led to severe reductions of bone marrow macrophages, erythroblasts, and in vivo island formation, indicating its role in postnatal murine bone marrow erythropoiesis [4]. In haematopoietic stem cells, Maea deletion severely impairs HSC quiescence and leads to a lethal myeloproliferative syndrome, suggesting its importance in maintaining HSC function [3]. Knockdown of Maea in glioblastoma xenograft tumors inhibited their growth, showing its role in promoting glioblastoma progression [1].

In conclusion, Maea is essential for various biological processes. KO/CKO mouse models have revealed its significance in diseases such as myeloproliferative syndrome and glioblastoma. Understanding Maea's functions provides insights into disease mechanisms and potential therapeutic targets.

References:

1. Zhou, Peijun, Peng, Xingzhi, Tang, Siyuan, Peng, Jinwu, Yang, Lifang. 2023. E3 ligase MAEA-mediated ubiquitination and degradation of PHD3 promotes glioblastoma progression. In Oncogene, 42, 1308-1320. doi:10.1038/s41388-023-02644-3. https://pubmed.ncbi.nlm.nih.gov/36882523/

2. Goto, Toshiyasu, Shibuya, Hiroshi. 2022. maea affects head formation through ß-catenin degradation during early Xenopus laevis development. In Development, growth & differentiation, 65, 29-36. doi:10.1111/dgd.12828. https://pubmed.ncbi.nlm.nih.gov/36444483/

3. Wei, Qiaozhi, Pinho, Sandra, Dong, Shuxian, Cuervo, Ana Maria, Frenette, Paul S. 2021. MAEA is an E3 ubiquitin ligase promoting autophagy and maintenance of haematopoietic stem cells. In Nature communications, 12, 2522. doi:10.1038/s41467-021-22749-1. https://pubmed.ncbi.nlm.nih.gov/33947846/

4. Wei, Qiaozhi, Boulais, Philip E, Zhang, Dachuan, Tanaka, Masato, Frenette, Paul S. 2019. Maea expressed by macrophages, but not erythroblasts, maintains postnatal murine bone marrow erythroblastic islands. In Blood, 133, 1222-1232. doi:10.1182/blood-2018-11-888180. https://pubmed.ncbi.nlm.nih.gov/30674470/