N-Acetyltransferase 9 ameliorates Aβ42-mediated neurodegeneration in the Drosophila eye.
Prajakta DeshpandeAnuradha Venkatakrishnan ChimataEmily SniderAditi SinghMadhuri Kango-SinghAmit SinghPublished in: Cell death & disease (2023)
Alzheimer's disease (AD), a progressive neurodegenerative disorder, manifests as accumulation of amyloid-beta-42 (Aβ42) plaques and intracellular accumulation of neurofibrillary tangles (NFTs) that results in microtubule destabilization. Targeted expression of human Aβ42 (GMR > Aβ42) in developing Drosophila eye retinal neurons results in Aβ42 plaque(s) and mimics AD-like extensive neurodegeneration. However, there remains a gap in our understanding of the underlying mechanism(s) for Aβ42-mediated neurodegeneration. To address this gap in information, we conducted a forward genetic screen, and identified N-acetyltransferase 9 (Mnat9) as a genetic modifier of GMR > Aβ42 neurodegenerative phenotype. Mnat9 is known to stabilize microtubules by inhibiting c-Jun-N- terminal kinase (JNK) signaling. We found that gain-of-function of Mnat9 rescues GMR > Aβ42 mediated neurodegenerative phenotype whereas loss-of-function of Mnat9 exhibits the converse phenotype of enhanced neurodegeneration. Here, we propose a new neuroprotective function of Mnat9 in downregulating the JNK signaling pathway to ameliorate Aβ42-mediated neurodegeneration, which is independent of its acetylation activity. Transgenic flies expressing human NAT9 (hNAT9), also suppresses Aβ42-mediated neurodegeneration thereby suggesting functional conservation in the interaction of fly Mnat9 or hNAT9 with JNK-mediated neurodegeneration. These studies add to the repertoire of molecular mechanisms that mediate cell death response following accumulation of Aβ42 and may provide new avenues for targeting neurodegeneration.
Keyphrases
- signaling pathway
- cell death
- endothelial cells
- induced apoptosis
- multiple sclerosis
- gene expression
- coronary artery disease
- poor prognosis
- genome wide
- healthcare
- epithelial mesenchymal transition
- dna methylation
- cancer therapy
- pi k akt
- high throughput
- cognitive decline
- induced pluripotent stem cells
- copy number
- cell proliferation
- long non coding rna
- blood brain barrier
- cell cycle arrest
- optic nerve