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Minaya, M.

Publications and source records attributed to Minaya, M..

4 recordsLinked to original sources

Parietal Cortex Transcriptomics Refines Parkinson Disease GWAS Nomination and Highlights STAT3 as a Putative Upstream Glial Regulator

Parkinson disease (PD) affects more than 1.1 million individuals in the United States and around 12 million worldwide. Although Genome Wide Association Studies (GWAS) have substantially advanced our understanding of PD genetic architecture, the regulatory mechanisms linking PD risk loci to disease-relevant gene expression remain incompletely characterized, limiting our ability to infer disease mechanisms from genetic associations. Here, we integrated disease-state parietal cortex transcriptomics with the International Parkinsons Disease Genomics Consortium (iPDGC) locus prioritization to refine PD gene nomination and identify biologically plausible candidates missed by GWAS-only approaches. Using bulk RNA-seq from 99 neuropathologically confirmed PD cases and 30 neuropathologically confirmed controls, we prioritized candidate genes across 78 loci and classified them according to concordance between genetic evidence and differential expression in diseased cortices. This integrative approach recovered candidate genes not captured by external GWAS-based prioritization methods and highlighted synaptic, lysosomal, and proteostasis pathways as major components of PD risk biology. Network and transcription factor analyses further suggested coordinated regulation of these genes, with STAT3 emerging as a putative upstream glial regulator. Together, these findings suggest that integrating disease-state transcriptomics with genetic prioritization can refine PD risk-gene nomination and uncover regulatory programs that may be missed by GWAS alone.

neuroscience↗

The NORAD-pumilio regulatory axis links lncRNA dysregulation to tau propagation-associated phenotypes

Long non-coding RNAs (lncRNAs) are increasingly implicated in neurodegenerative disease, yet their roles in tauopathy remain poorly understood. Here, we defined the lncRNA landscape across iPSC-derived neurons, astrocytes, and microglia harboring the frontotemporal dementia-associated MAPT IVS10+16 mutation and investigated how lncRNA dysregulation interfaces with tau pathology. Transcriptomic analyses revealed extensive cell-type specific lncRNA expression changes, with neurons exhibiting the greatest degree of mutation-associated remodeling. Comparative analyses with MAPT IVS10+16 patient brain tissue identified NORAD and MIR22HG as lncRNAs significantly dysregulated across all three cell types and human brains. NORAD was also altered in Alzheimers disease and Parkinsons disease brains, suggesting a broader role in neurodegenerative disease. Mechanistically, NORAD-associated protein networks converged on pathways related to RNA regulation, cytoskeletal organization, proteostasis, and tau interaction networks. Given the established role of NORAD in regulating PUM1 and PUM2 RNA-binding (pumilio) proteins, we examined the NORAD-pumilio axis and identified enrichment of pumilio-associated pathways linked to autophagy, endocytosis, proteostasis, and cytoskeletal regulation. NORAD depletion reduced tau seeding and uptake, whereas functional depletion of PUM1 or PUM2 increased both processes, supporting an antagonistic relationship between NORAD and pumilio signaling in modulation of tau aggregation. Together, these findings identify widespread lncRNA dysregulation across neural cell types in the setting of a MAPT mutation and nominate the NORAD-pumilio axis as a regulatory pathway linking RNA homeostasis and tau propagation biology.

neuroscience↗

Autophagic enhancer rescues Tau accumulation in a stem cell model of frontotemporal dementia

Tau degradation is disrupted in neurodegenerative tauopathies, such as frontotemporal dementia (FTD), which may contribute to Tau aggregation. The prevailing hypothesis has been that Tau degradation is stymied due to an imbalance in proteostasis that occurs with age. Here, we used Airyscan super resolution imaging to illustrate that a pathogenic FTD mutation in the MAPT gene, which encodes Tau, is sufficient to alter multiple steps of the autophagy lysosomal pathway and impair Tau degradation. We discovered lysosomes clogged with both Tau and phosphorylated Tau, stalled lysosome motility, disrupted molecular motors, enhanced autophagic flux, and slowed cargo degradation in mutant Tau neurons. Treatment of mutant Tau neurons with a small molecule autophagy enhancer drug increases autophagic flux and cargo degradation, reduces phospho-Tau levels, and reduces Tau accumulation in lysosomes without restoring defects in lysosomal motility. This study reveals novel effects of mutant Tau and provides a window through which therapeutic treatments targeting autophagy may promote Tau homeostasis.

neuroscience↗

m6A-dependent circular RNA formation mediatestau-induced neurotoxicity

Circular RNAs (circRNAs), covalently closed RNA molecules that form due to back-splicing of RNA transcripts, have recently been implicated in Alzheimers disease and related tauopathies. circRNAs are regulated by N6-methyladenosine (m6A) RNA methylation, can serve as "sponges" for proteins and RNAs, and can be translated into protein via a cap-independent mechanism. Mechanisms underlying circRNA dysregulation in tauopathies and causal relationships between circRNA and neurodegeneration are currently unknown. In the current study, we aimed to determine whether pathogenic forms of tau drive circRNA dysregulation and whether such dysregulation causally mediates neurodegeneration. We identify circRNAs that are differentially expressed in the brain of a Drosophila model of tauopathy and in induced pluripotent stem cell (iPSC)-derived neurons carrying a tau mutation associated with autosomal dominant tauopathy. We leverage Drosophila to discover that depletion of circular forms of muscleblind (circMbl), a circRNA that is particularly abundant in brains of tau transgenic Drosophila, significantly suppresses tau neurotoxicity, suggesting that tau-induced circMbl elevation is neurotoxic. We detect a general elevation of m6A RNA methylation and circRNA methylation in tau transgenic Drosophila and find that tau-induced m6A methylation is a mechanistic driver of circMbl formation. Interestingly, we find that circRNA and m6A RNA accumulate within nuclear envelope invaginations of tau transgenic Drosophila and in iPSC-derived cerebral organoid models of tauopathy. Taken together, our studies add critical new insight into the mechanisms underlying circRNA dysregulation in tauopathy and identify m6A-modified circRNA as a causal factor contributing to neurodegeneration. These findings add to a growing literature implicating pathogenic forms of tau as drivers of altered RNA metabolism.

neuroscience↗