Mrps9, or mitochondrial ribosomal protein S9, is a crucial component for the structural and functional integrity of the mitoribosome complex [2]. It plays a pivotal role in regulating mitochondrial function and maintaining structural integrity [1]. Bioinformatic and pathway analysis suggest its association with the PI3K/Akt/mTOR signaling pathway [1].

In ischemic stroke research, bioinformatic analysis revealed significant underexpression of MRPS9 in patients. In vitro experiments with HN cells under oxygen-glucose deprivation/reoxygenation (OGD/R) treatment showed reduced MRPS9 expression, decreased cell viability, and increased apoptosis. Overexpression of MRPS9 mitigated these effects. In mouse models of middle cerebral artery occlusion/reperfusion (MCAO/R), MRPS9 expression was lower compared to sham surgery groups. Inhibition of the PI3K/Akt/mTOR pathway reversed the protective effect of MRPS9 overexpression, indicating that MRPS9 overexpression inhibits this pathway activation, protecting neurons from apoptosis and impeding ischemic stroke progression [1].

In conclusion, Mrps9 is essential for mitoribosome function and mitochondrial integrity. Through regulating the PI3K/Akt/mTOR pathway, Mrps9 plays a protective role in neuronal apoptosis during ischemic stroke, as demonstrated by in vitro and in vivo models. Understanding Mrps9 provides new perspectives for the diagnosis and treatment of ischemic stroke [1].

References:

1. Jiang, Jina, Qi, Tingting, Li, Li, Ma, Xiaoqing, Qin, Yinghui. 2024. MRPS9-Mediated Regulation of the PI3K/Akt/mTOR Pathway Inhibits Neuron Apoptosis and Protects Ischemic Stroke. In Journal of molecular neuroscience : MN, 74, 23. doi:10.1007/s12031-024-02197-4. https://pubmed.ncbi.nlm.nih.gov/38381220/

2. Cheong, Agnes, Lingutla, Ranjana, Mager, Jesse. 2020. Expression analysis of mammalian mitochondrial ribosomal protein genes. In Gene expression patterns : GEP, 38, 119147. doi:10.1016/j.gep.2020.119147. https://pubmed.ncbi.nlm.nih.gov/32987154/