Ubiquitinome Profiling Reveals in Vivo UBE2D3 Targets and Implicates UBE2D3 in Protein Quality Control.

Ubiquitination has crucial roles in many cellular processes, and dysregulation of ubiquitin machinery enzymes can result in various forms of pathogenesis. Cells only have a limited set of ubiquitin-conjugating (E2) enzymes to support the ubiquitination of many cellular targets. As individual E2 enzymes have many different substrates and interactions between E2 enzymes and their substrates can be transient, it is challenging to define all in vivo substrates of an individual E2 and the cellular processes it affects. Particularly challenging in this respect is UBE2D3, an E2 enzyme with promiscuous activity in vitro but less defined roles in vivo. Here, we set out to identify in vivo targets of UBE2D3 by using stable isotope labeling by amino acids in cell culture-based and label-free quantitative ubiquitin diGly proteomics to study global proteome and ubiquitinome changes associated with UBE2D3 depletion. UBE2D3 depletion changed the global proteome, with the levels of proteins from metabolic pathways, in particular retinol metabolism, being the most affected. However, the impact of UBE2D3 depletion on the ubiquitinome was much more prominent. Interestingly, molecular pathways related to mRNA translation were the most affected. Indeed, we find that ubiquitination of the ribosomal proteins RPS10 and RPS20, critical for ribosome-associated protein quality control, is dependent on UBE2D3. We show by Targets of Ubiquitin Ligases Identified by Proteomics 2 methodology that RPS10 and RPS20 are direct targets of UBE2D3 and demonstrate that the catalytic activity of UBE2D3 is required to ubiquitinate RPS10 in vivo. In addition, our data suggest that UBE2D3 acts at multiple levels in autophagic protein quality control. Collectively, our findings show that depletion of an E2 enzyme in combination with quantitative diGly-based ubiquitinome profiling is a powerful tool to identify new in vivo E2 substrates, as we have done here for UBE2D3. Our work provides an important resource for further studies on the in vivo functions of UBE2D3.

Medical image diagnosis based on adaptive Hybrid Quantum CNN.

Hybrid quantum systems have shown promise in image classification by combining the strengths of both classical and quantum algorithms. These systems leverage the parallel processing power of quantum computers to perform complex computations while utilizing classical algorithms to handle the vast amounts of data involved in imaging. The hybrid approach is intended to improve accuracy and speed compared to traditional classical methods. Further research and development in this area can revolutionize the way medical images are classified and help improve patient diagnosis and treatment. The use of Conventional Neural Networks (CNN) for the classification and diagnosis of medical images using big datasets requires, in most cases, the use of special high-performance computing machines, which are very expensive and hard to access by most researchers. A new form of Machine Learning (ML), Quantum machine learning (QML), is being introduced as an emerging strategy to overcome this problem. A hybrid quantum-classical CNN uses both quantum and classical convolution layers designed to use a parameterized quantum circuit. This means that the computing model utilizes a quantum circuits approach to construct QML algorithms, which are then used to transform the quantum state to extract image hidden features. This computational acceleration is expected to achieve better algorithm performance than classical CNNs. This study intends to evaluate the performance of a Hybrid Quantum CNN (HQCNN) against a conventional CNN. This is followed by some optimizer modifications for both proposed and classical CNN methods to investigate the possible further improvement of their performance. The optimizer modification is based on forcing the optimizer to be directly adaptive to model accuracy. The optimizer adaptiveness is based on the development of an optimizer with a loss base adaptive momentum. Several algorithms are developed to achieve the above-mentioned goals, including CNN, QCNN, CNN with the adaptive optimizer, and QCNN with the Adaptive optimizer. The four algorithms are tested against a Kaggle brain dataset containing over 7000 samples. The test results show the hybrid quantum circuit algorithm outperformed the conventional CNN algorithm. The performance of both algorithms was further improved by using a fully adaptive SGD optimizer.

Quantum Random Access Memory for Dummies.

Quantum Random Access Memory (QRAM) has the potential to revolutionize the area of quantum computing. QRAM uses quantum computing principles to store and modify quantum or classical data efficiently, greatly accelerating a wide range of computer processes. Despite its importance, there is a lack of comprehensive surveys that cover the entire spectrum of QRAM architectures. We fill this gap by providing a comprehensive review of QRAM, emphasizing its significance and viability in existing noisy quantum computers. By drawing comparisons with conventional RAM for ease of understanding, this survey clarifies the fundamental ideas and actions of QRAM. QRAM provides an exponential time advantage compared to its classical counterpart by reading and writing all data at once, which is achieved owing to storage of data in a superposition of states. Overall, we compare six different QRAM technologies in terms of their structure and workings, circuit width and depth, unique qualities, practical implementation, and drawbacks. In general, with the exception of trainable machine learning-based QRAMs, we observe that QRAM has exponential depth/width requirements in terms of the number of qubits/qudits and that most QRAM implementations are practical for superconducting and trapped-ion qubit systems.

A Programmable Crypto-Processor for National Institute of Standards and Technology Post-Quantum Cryptography Standardization Based on the RISC-V Architecture.

The advancement of quantum computing threatens the security of conventional public-key cryptosystems. Post-quantum cryptography (PQC) was introduced to ensure data confidentiality in communication channels, and various algorithms are being developed. The National Institute of Standards and Technology (NIST) has initiated PQC standardization, and the selected algorithms for standardization and round 4 candidates were announced in 2022. Due to the large memory footprint and highly repetitive operations, there have been numerous attempts to accelerate PQC on both hardware and software. This paper introduces the RISC-V instruction set extension for NIST PQC standard algorithms and round 4 candidates. The proposed programmable crypto-processor can support a wide range of PQC algorithms with the extended RISC-V instruction set and demonstrates significant reductions in code size, the number of executed instructions, and execution cycle counts of target operations in PQC algorithms of up to 79%, 92%, and 87%, respectively, compared to RV64IM with optimization level 3 (-O3) in the GNU toolchain.

Protein Aggregates and Aggrephagy in Myopathies.

A number of muscular disorders are hallmarked by the aggregation of misfolded proteins within muscle fibers. A specialized form of macroautophagy, termed aggrephagy, is designated to remove and degrade protein aggregates. This review aims to summarize what has been studied so far about the direct involvement of aggrephagy and the activation of the key players, among others, p62, NBR1, Alfy, Tollip, Optineurin, TAX1BP1 and CCT2 in muscular diseases. In the first part of the review, we describe the aggrephagy pathway with the involved proteins; then, we illustrate the muscular disorder histologically characterized by protein aggregates, highlighting the role of aggrephagy pathway abnormalities in these muscular disorders.

Pathogenic variants of Valosin-containing protein induce lysosomal damage and transcriptional activation of autophagy regulators in neuronal cells.

AIM: Mutations in the valosin-containing protein (VCP) gene cause various lethal proteinopathies that mainly include inclusion body myopathy with Paget's disease of bone and frontotemporal dementia (IBMPFD) and amyotrophic lateral sclerosis (ALS). Different pathological mechanisms have been proposed. Here, we define the impact of VCP mutants on lysosomes and how cellular homeostasis is restored by inducing autophagy in the presence of lysosomal damage. METHODS: By electron microscopy, we studied lysosomal morphology in VCP animal and motoneuronal models. With the use of western blotting, real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence and filter trap assay, we evaluated the effect of selected VCP mutants in neuronal cells on lysosome size and activity, lysosomal membrane permeabilization and their impact on autophagy. RESULTS: We found that VCP mutants induce the formation of aberrant multilamellar organelles in VCP animal and cell models similar to those found in patients with VCP mutations or with lysosomal storage disorders. In neuronal cells, we found altered lysosomal activity characterised by membrane permeabilization with galectin-3 redistribution and activation of PPP3CB. This selectively activated the autophagy/lysosomal transcriptional regulator TFE3, but not TFEB, and enhanced both SQSTM1/p62 and lipidated MAP1LC3B levels inducing autophagy. Moreover, we found that wild type VCP, but not the mutants, counteracted lysosomal damage induced either by trehalose or by a mutant form of SOD1 (G93A), also blocking the formation of its insoluble intracellular aggregates. Thus, chronic activation of autophagy might fuel the formation of multilamellar bodies. CONCLUSION: Together, our findings provide insights into the pathogenesis of VCP-related diseases, by proposing a novel mechanism of multilamellar body formation induced by VCP mutants that involves lysosomal damage and induction of lysophagy.

Spatial sequestration of misfolded proteins as an active chaperone-mediated process during heat stress.

Under thermal stress, different protein quality control (PQC) strategies are activated to maintain an intact proteome, which may vary from one model system to another. Hence thermo-sensitive proteins that lose their active conformation might be refolded with the aid of chaperones or removed by the ubiquitin-proteasome system or the process of autophagy. We have recently developed thermo-sensitive reporters to study PQC in fission yeast and shown the relevance of a third adaptation strategy: the sequestration of misfolded proteins into inclusions which will prevent a rapid degradation and allow the refolding once stress ends. These protein inclusions, protein aggregate centers (PACs), contain a broad spectrum of misfolding/aggregation-prone proteins and chaperones involved in their assembly or dissolution. The chaperone couple Mas5/Ssa2 plays a crucial role in PAC formation, whereas the Hsp104 chaperone promotes their disassembly. The absence of aggregates observed in cells lacking Mas5 could be also explained by the activation of the transcription factor Hsf1 and the induction of chaperone genes, we have excluded this possibility here demonstrating that increased Hsf1 activity and the subsequent overexpression of chaperones do not prevent the assembly of protein aggregates. Protein deposition at certain locations also constitutes a tactic to inactivate proteins temporally. This is the case of Pyp1, the main phosphatase of the stress response kinase Sty1. Upon stress imposition, misfolded Pyp1 is sequestered into cytosolic protein foci while active Sty1 at the nucleus switches on the transcriptional response. In conclusion, we propose that the assembly of aggregation-like foci, PACs in fission yeast, is a crucial PQC strategy during heat stress, and that the Hsp40 chaperone Mas5 is required for PAC assembly and connects physiological and heat-shock triggered PQC.

MPSR1 is a cytoplasmic PQC E3 ligase for eliminating emergent misfolded proteins in Arabidopsis thaliana.

Ubiquitin E3 ligases are crucial for eliminating misfolded proteins before they form cytotoxic aggregates that threaten cell fitness and survival. However, it remains unclear how emerging misfolded proteins in the cytoplasm can be selectively recognized and eliminated by E3 ligases in plants. We found that Misfolded Protein Sensing RING E3 ligase 1 (MPSR1) is an indispensable E3 ligase required for plant survival after protein-damaging stress. Under no stress, MPSR1 is prone to rapid degradation by the 26S proteasome, concealing its protein quality control (PQC) E3 ligase activity. Upon proteotoxic stress, MPSR1 directly senses incipient misfolded proteins and tethers ubiquitins for subsequent degradation. Furthermore, MPSR1 sustains the structural integrity of the proteasome complex at the initial stage of proteotoxic stress. Here, we suggest that the MPSR1 pathway is a constitutive mechanism for proteostasis under protein-damaging stress, as a front-line surveillance system in the cytoplasm.

On Global Quantum Communication Networking.

Research in quantum communications networks (QCNs), where multiple users desire to generate or transmit common quantum-secured information, is still in its beginning stage. To solve for the problems of both discrete variable- and continuous variable-quantum key distribution (QKD) schemes in a simultaneous manner as well as to enable the next generation of quantum communication networking, in this Special Issue paper we describe a scenario where disconnected terrestrial QCNs are coupled through low Earth orbit (LEO) satellite quantum network forming heterogeneous satellite-terrestrial QCN. The proposed heterogeneous QCN is based on the cluster state approach and can be used for numerous applications, including: (i) to teleport arbitrary quantum states between any two nodes in the QCN; (ii) to enable the next generation of cyber security systems; (iii) to enable distributed quantum computing; and (iv) to enable the next generation of quantum sensing networks. The proposed QCNs will be robust against various channel impairments over heterogeneous links. Moreover, the proposed QCNs will provide an unprecedented security level for 5G+/6G wireless networks, Internet of Things (IoT), optical networks, and autonomous vehicles, to mention a few.

Performance Enhancement of Interdigital Electrode-Piezoelectric Quartz Crystal (IDE-PQC) Salt Concentration Sensor by Increasing the Electrode Area of Piezoelectric Quartz Crystal (PQC).

In this paper, a new approach to enhance the performance of the interdigital electrode-piezoelectric quartz crystal (IDE-PQC) salt solution concentration sensor by modifying the electrode area of PQC was proposed. Equivalent circuit analysis showed that the static capacitor (C0) which is related to the electrode area of PQC directly affected the response sensitivity of the IDE-PQC sensor. Further, the sensing responses of IDE-PQC sensors to various concentrations of salt solution were measured. Three kinds of salt solution, including NaCl, KCl, and Na2SO4, were adpoted to evaluate the sensing performances of the IDE-PQC sensors. The experimental results also indicated that increasing the electrode area of PQC can enhance the sensitivity response of the IDE-PQC sensors to the change of salt solution concentration. For example, the detection sensitivity of the IDE-PQC sensor with an electrode diameter of 5 mm was about three times larger than that of the sensor with an electrode diameter of 3 mm. Meanwhile, we found that the frequency stability of the IDE-PQC sensor was also improved by increasing the electrode area of PQC. In addition, the influence of the electrode area of PQC on the repeatability and the transient response of IDE-PQC salt solution concentration sensor were also studied. This work demonstrates simple and cost-effective method to achieve the performance enhancement of IDE-PQC salt solution concentration sensor by modifying the electrode area of PQC.

Protein aggregation propensity is a crucial determinant of intracellular inclusion formation and quality control degradation.

Protein aggregation is linked to many pathological conditions, including several neurodegenerative diseases. The aggregation propensities of proteins are thought to be controlled to a large extent by the physicochemical properties encoded in the primary sequence. We have previously exploited a set of amyloid ß peptide (Aß42) variants exhibiting a continuous gradient of intrinsic aggregation propensities to demonstrate that this rule applies in vivo in bacteria. In the present work we have characterized the behavior of these Aß42 mutants when expressed in yeast. In contrast to bacteria, the intrinsic aggregation propensity is gated by yeast, in such a way that this property correlates with the formation of intracellular inclusions only above a specific aggregation threshold. Proteins displaying solubility levels above this threshold escape the inclusion formation pathway. In addition, the most aggregation-prone variants are selectively cleared by the yeast quality control degradation machinery. Thus, both inclusion formation and proteolysis target the same aggregation-prone variants and cooperate to minimize the presence of these potentially dangerous species in the cytosol. The demonstration that sorting to these pathways in eukaryotes is strongly influenced by protein primary sequence should facilitate the development of rational approaches to predict and hopefully prevent in vivo protein deposition.

Specific inhibition of hamster prion protein translocation by the dodecadepsipeptide valinomycin.

Regulating the entry of secretory and membrane proteins into the ER is shown to be an important physiological process, in terms of controlling quantity, localization and therefore function of target proteins. However, few small molecule modulators are available to pharmacologically regulate translocation of a specific protein. Here, we identified a small molecule that specifically inhibits pathogenic PrP biosynthesis using a highly sensitive and reproducible assay based on the fluorogenic substrate reporter PrP. This molecule specifically destabilized the signal peptide of PrP, leading to cotranslational rerouting of a significant amount of nascent PrP to proteasome-dependent degradation pathway in the cytosol. This study suggests that regulating differential translocation efficiency attributable to sequence diversity in signal peptides of disease-causing secretory and membrane proteins using cell-permeable small molecules may be a potential therapeutic approach for diseases associated with impaired protein biogenesis.

Less is better: various means to reduce protein load in the endoplasmic reticulum.

The endoplasmic reticulum (ER) is an important organelle that controls the intracellular and extracellular environments. The ER is responsible for folding almost one-third of the total protein population in the eukaryotic cell. Disruption of ER-protein folding is associated with numerous human diseases, including metabolic disorders, neurodegenerative diseases, and cancer. During ER perturbations, the cells deploy various mechanisms to increase the ER-folding capacity and reduce ER-protein load by minimizing the number of substrates entering the ER to regain homeostasis. These mechanisms include signaling pathways, degradation mechanisms, and other processes that mediate the reflux of ER content to the cytosol. In this review, we will discuss the recent discoveries of five different ER quality control mechanisms, including the unfolded protein response (UPR), ER-associated-degradation (ERAD), pre-emptive quality control, ER-phagy and ER to cytosol signaling (ERCYS). We will discuss the roles of these processes in decreasing ER-protein load and inter-mechanism crosstalk.

Software implementation of systematic polar encoding based PKC-SPE cryptosystem for quantum cybersecurity.

The ever-growing threats in cybersecurity growing with the rapid development of quantum computing, necessitates the development of robust and quantum-resistant cryptographic systems. This paper introduces a novel cryptosystem, Public Key Cryptosystem based on Systematic Polar Encoding (PKC-SPE), based on the combination of systematic polar encoding and public-key cryptographic principles. The Systematic Polar Encoding (SPE), derived from the well-established field of polar codes, serves as the foundation for this proposed cryptographic scheme. Here, we have used MATLAB Software to introduce and implement the PKC-SPE Cryptosystem. The paper examines key generation, encryption, and decryption algorithms, providing insights into the adaptability and efficiency of systematic polar encoding in public-key cryptography. We assess the efficiency of the PKC-SPE Cryptosystem in three aspects: key size, computational complexity, and system implementation timings. In addition, we compare the PKC-SPE Cryptosystem with PKC-PC cryptosystem and find that it has reduced key sizes ( P r = 0.8436 kbytes). The results obtained through simulations validate the effectiveness of the proposed cryptosystem and highlighting its potential for integration into real-world communication systems. Thus, in the paradigm shift to quantum computing, the PKC-SPE cryptosystem emerges as a promising candidate to secure digital communication in the quantum computing era.

Glycation in the cardiomyocyte.

Glycation is a protein post-translational modification that can occur on lysine and arginine residues as a result of a non-enzymatic process known as the Maillard reaction. This modification is irreversible, so the only way it can be removed is by protein degradation and replacement. Small reactive carbonyl species, glyoxal and methylglyoxal, are the primary glycating agents and are elevated in several conditions associated with an increased risk of cardiovascular disease, including diabetes, rheumatoid arthritis, smoking, and aging. Thus, how protein glycation impacts the cardiomyocyte is of particular interest, to both understand how these conditions increase the risk of cardiovascular disease and how glycation might be targeted therapeutically. Glycation can affect the cardiomyocyte through extracellular mechanisms, including RAGE-based signaling, glycation of the extracellular matrix that modifies the mechanical environment, and signaling from the vasculature. Intracellular glycation of the cardiomyocyte can impact calcium handling, protein quality control and cell death pathways, as well as the cytoskeleton, resulting in a blunted contractility. While reducing protein glycation and its impact on the heart has been an active area of drug development, multiple clinical trials have had mixed results and these compounds have not been translated to the clinic-highlighting the challenges of modulating myocyte glycation. Here we will review protein glycation and its effects on the cardiomyocyte, therapeutic attempts to reverse these, and offer insight as to the future of glycation studies and patient treatment.

Patient-Centric Interoperability and Cybersecurity for Cross-Border Healthcare.

In Web 3.0 the user owns the information. Decentralized Identity Documents (DID documents) allow users to create their own digital identity and decentralized cryptographic material resistant to quantum computing. A patient's DID document also contains a unique identifier for cross-border healthcare, endpoints for receiving DIDComm messages and for SOS services, and additional identifiers (passport, etc.). We propose a blockchain for cross-border healthcare to store the evidence of different electronic, physical identities, and identifiers, but also the rules approved by the patient or legal guardians to access patient data. The International Patient Summary (IPS) is the de facto standard for cross-border healthcare and includes an index of information classified into sections (HL7 FHIR Composition) that healthcare professionals and services can update and read on the patient's SOS service, then retrieving all the necessary patient information from the different FHIR API endpoints of different healthcare providers according to the approved rules.

The Hsp70 and JDP proteins: Structure-function perspective on molecular chaperone activity.

Proteins are the most structurally diverse cellular biomolecules that act as molecular machines driving essential activities of all living organisms. To be functional, most of the proteins need to fold into a specific three-dimensional structure, which on one hand should be stable enough to oppose disruptive conditions and on the other hand flexible enough to allow conformational dynamics necessary for their biological functions. This compromise between stability and dynamics makes proteins susceptible to stress-induced misfolding and aggregation. Moreover, the folding process itself is intrinsically prone to conformational errors. Molecular chaperones are proteins that mitigate folding defects and maintain the structural integrity of the cellular proteome. Promiscuous Hsp70 chaperones are central to these processes and their activity depends on the interaction with obligatory J-domain protein (JDP) partners. In this review, we discuss structural aspects of Hsp70s, JDPs, and their interaction in the context of biological activities.

Abnormal triaging of misfolded proteins by adult neuronal ceroid lipofuscinosis-associated DNAJC5/CSPα mutants causes lipofuscin accumulation.

Mutations in DNAJC5/CSPα are associated with adult neuronal ceroid lipofuscinosis (ANCL), a dominant-inherited neurodegenerative disease featuring lysosome-derived autofluorescent storage materials (AFSMs) termed lipofuscin. Functionally, DNAJC5 has been implicated in chaperoning synaptic proteins and in misfolding-associated protein secretion (MAPS), but how DNAJC5 dysfunction causes lipofuscinosis and neurodegeneration is unclear. Here we report two functionally distinct but coupled chaperoning activities of DNAJC5, which jointly regulate lysosomal homeostasis: While endolysosome-associated DNAJC5 promotes ESCRT-dependent microautophagy, a fraction of perinuclear and non-lysosomal DNAJC5 mediates MAPS. Functional proteomics identifies a previously unknown DNAJC5 interactor SLC3A2/CD98hc that is essential for the perinuclear DNAJC5 localization and MAPS but dispensable for microautophagy. Importantly, uncoupling these two processes, as seen in cells lacking SLC3A2 or expressing ANCL-associated DNAJC5 mutants, generates DNAJC5-containing AFSMs resembling NCL patient-derived lipofuscin and induces neurodegeneration in a Drosophila ANCL model. These findings suggest that MAPS safeguards microautophagy to avoid DNAJC5-associated lipofuscinosis and neurodegeneration.Abbreviations: 3-MA: 3-methyladenine; ACTB: actin beta; AFSM: autofluorescent storage materials; ANCL: adult neuronal ceroid lipofuscinosis; Baf. A1: bafilomycin A1; CLN: ceroid lipofuscinosis neuronal; CLU: clusterin; CS: cysteine string domain of DNAJC5/CSPα; CUPS: compartment for unconventional protein secretion; DN: dominant negative; DNAJC5/CSPα: DnaJ heat shock protein family (Hsp40) member C5; eMI: endosomal microautophagy; ESCRT: endosomal sorting complex required for transport; GFP: green fluorescent protein; HSPA8/HSC70: heat shock protein family A (Hsp70) member 8; INCL: infant neuronal ceroid lipofuscinosis; JNCL: juvenile neuronal ceroid lipofuscinosis; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LAPTM4B: lysosomal protein transmembrane 4 beta; LN: linker domain of DNAJC5/CSPα; MAPS: misfolding-associated protein secretion; mCh/Ch: mCherry; mCi/Ci: mCitrine; MTOR: mechanistic target of rapamycin kinase; NCL: neuronal ceroid lipofuscinosis; PPT1: palmitoyl-protein thioesterase 1; PQC: protein quality control; SBP: streptavidin binding protein; SGT: small glutamine-rich tetratricopeptide repeat; shRNA: short hairpin RNA; SLC3A2/CD98hc: solute carrier family 3 member 2; SNCA/α-synuclein: synuclein alpha; TMED10: transmembrane p24 trafficking protein 10; UV: ultraviolet; VPS4: vacuolar protein sorting 4 homolog; WT: wild type.

Volleying plasma membrane proteins from birth to death: Role of J-domain proteins.

The function, stability, and turnover of plasma membrane (PM) proteins are crucial for cellular homeostasis. Compared to soluble proteins, quality control of plasma membrane proteins is extremely challenging. Failure to meet the high quality control standards is detrimental to cellular and organismal health. J-domain proteins (JDPs) are among the most diverse group of chaperones that collaborate with other chaperones and protein degradation machinery to oversee cellular protein quality control (PQC). Although fragmented, the available literature from different models, including yeast, mammals, and plants, suggests that JDPs assist PM proteins with their synthesis, folding, and trafficking to their destination as well as their degradation, either through endocytic or proteasomal degradation pathways. Moreover, some JDPs interact directly with the membrane to regulate the stability and/or functionality of proteins at the PM. The deconvoluted picture emerging is that PM proteins are relayed from one JDP to another throughout their life cycle, further underscoring the versatility of the Hsp70:JDP machinery in the cell.

Multiple checkpoints of protein clearance machinery are modulated by a common microRNA, miR-4813-3p, through its putative target genes: Studies employing transgenic C. elegans model.

In order to maintain cellular homeostasis and a healthy state, aberrant and aggregated proteins are to be recognized and rapidly cleared from cells. Parkinson's disease, known to be associated with multiple factors; presents with impaired clearance of aggregated alpha synuclein as a key factor. We endeavored to study microRNA molecules with potential role on regulating multiple checkpoints of protein quality control within cells. Carrying out global miRNA profiling in a transgenic C. elegans model that expresses human alpha synuclein, we identified novel miRNA, miR-4813-3p, as a significantly downregulated molecule. Further studying its putative downstream target genes, we were able to mechanistically characterize six genes gbf-1, vha-5, cup-5, cpd-2, acs-1 and C27A12.7, which relate to endpoints associated with alpha synuclein expression, oxidative stress, locomotory behavior, autophagy and apoptotic pathways. Our study reveals the novel role of miR-4813-3p and provides potential functional characterization of its putative target genes, in regulating the various pathways associated with PQC network. miR-4813-3p modulates ERUPR, MTUPR, autophagosome-lysosomal-pathway and the ubiquitin-proteasomal-system, making this molecule an interesting target for further studies towards therapeutically addressing multifactorial aspect of Parkinson's disease.