Publications by authors named "Ali Shaib"

Transplantation of induced pluripotent stem cell-derived neural cells represents a promising strategy for treating neurodegenerative diseases. However, reprogramming of somatic cells and their subsequent neural differentiation is complex and time-consuming, thereby impeding autologous applications. Recently, direct transcription factor-based conversion of blood cells into induced neural stem cells (iNSCs) has emerged as a potential alternative.

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Article Synopsis
  • The MJF-14 PLA is a new technique for detecting α-synuclein aggregates, demonstrating high specificity and sensitivity for non-Lewy body pathology.
  • This assay shows a strong correlation between α-synuclein aggregation and specific conditions in both cell cultures and human neuronal samples linked to neurodegenerative diseases.
  • The findings indicate that a significant amount of α-synuclein pathology occurs before the formation of Lewy bodies in diseases such as Parkinson's, suggesting the need for further research using brain samples.
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  • Fluorescence microscopy has advanced to subnanometer resolution but struggles to visualize single proteins or small complexes; researchers have developed a method called ONE microscopy to address this.
  • ONE microscopy expands specimens, tags them with fluorophores, and captures videos to analyze fluorescence fluctuations, allowing for the visualization of individual proteins' shapes at around 1-nm resolution.
  • This technique can observe protein conformational changes and has potential applications in clinical settings, such as analyzing protein aggregates in cerebrospinal fluid from Parkinson's patients, bridging high-resolution biology and light microscopy for new discoveries.
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Neuronal transmission relies on the regulated secretion of neurotransmitters, which are packed in synaptic vesicles (SVs). Hundreds of SVs accumulate at synaptic boutons. Despite being held together, SVs are highly mobile, so that they can be recruited to the plasma membrane for their rapid release during neuronal activity.

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Advances in genome sequencing technologies have favored the identification of rare mutations linked to neurological disorders in humans. Recently, a autosomal dominant mutation in was identified (NM_052876.3: c.

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Expansion microscopy (ExM) improves imaging quality by physically enlarging the biological specimens. In principle, combining a large expansion factor with optical super-resolution should provide extremely high imaging precision. However, large expansion factors imply that the expanded specimens are dim and are therefore poorly suited for optical super-resolution.

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Quantum computers have enabled solving problems beyond the current machines' capabilities. However, this requires handling noise arising from unwanted interactions in these systems. Several protocols have been proposed to address efficient and accurate quantum noise profiling and mitigation.

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To maintain homeostasis, the body, including the brain, reprograms its metabolism in response to altered nutrition or disease. However, the consequences of these challenges for the energy metabolism of the different brain cell types remain unknown. Here, we generated a proteome atlas of the major central nervous system (CNS) cell types from young and adult mice, after feeding the therapeutically relevant low-carbohydrate, high-fat ketogenic diet (KD) and during neuroinflammation.

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The neurotransmitter dopamine (DA) controls multiple behaviors and is perturbed in several major brain diseases. DA is released from large populations of specialized structures called axon varicosities. Determining the DA release mechanisms at such varicosities is essential for a detailed understanding of DA biology and pathobiology but has been limited by the low spatial resolution of DA detection methods.

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Both paralogs of the calcium-dependent activator protein for secretion (CAPS) are required for exocytosis of synaptic vesicles (SVs) and large dense core vesicles (LDCVs). Despite approximately 80% sequence identity, CAPS1 and CAPS2 have distinct functions in promoting exocytosis of SVs and LDCVs in dorsal root ganglion (DRG) neurons. However, the molecular mechanisms underlying these differences remain enigmatic.

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Background: Pharmaceutical intervention in the CNS is hampered by the shielding function of the blood-brain barrier (BBB). To induce clinical anesthesia, general anesthetics such as isoflurane readily penetrate the BBB. Here, we investigated whether isoflurane can be utilized for therapeutic drug delivery.

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Different families of auxiliary subunits regulate the function and trafficking of native α (AMPA) receptors in the central nervous system. While a facilitatory role of auxiliary subunits in ER export and forward trafficking of newly synthesized AMPA receptors is firmly established, it is unclear whether auxiliary subunits also control endosomal receptor turnover in dendrites. Here, we manipulated the composition of AMPA receptor complexes in cultured hippocampal neurons by overexpression of two auxiliary subunits, (TARP) γ-8 or (CKAMP) 44a, and monitored dendritic receptor cycling in live-cell imaging experiments.

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iPSC-derived human neurons are expected to revolutionize studies on brain diseases, but their functional heterogeneity still poses a problem. Key sources of heterogeneity are the different cell culture systems used. We show that an optimized autaptic culture system, with single neurons on astrocyte feeder islands, is well suited to culture, and we analyze human iPSC-derived neurons in a standardized, systematic, and reproducible manner.

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SNAP-25 is an essential component of SNARE complexes driving fast Ca-dependent exocytosis. Yet, the functional implications of the tandem-like structure of SNAP-25 are unclear. Here, we have investigated the mechanistic role of the acylated "linker" domain that concatenates the two SNARE motifs within SNAP-25.

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The two paralogs of the calcium-dependent activator protein for secretion (CAPS) are priming factors for synaptic vesicles (SVs) and neuropeptide containing large dense-core vesicles (LDCVs). Yet, it is unclear whether CAPS1 and CAPS2 regulate exocytosis of these two vesicle types differentially in dorsal root ganglion (DRG) neurons, wherein synaptic transmission and neuropeptide release are of equal importance. These sensory neurons transfer information from the periphery to the spinal cord (SC), releasing glutamate as the primary neurotransmitter, with co-transmission via neuropeptides in a subset of so called peptidergic neurons.

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Peptidergic dorsal root ganglion (DRG) neurons transmit sensory and nociceptive information from the periphery to the central nervous system. Their synaptic activity is profoundly affected by neuromodulatory peptides stored and released from large dense-core vesicles (LDCVs). However, the mechanism of peptide secretion from DRG neurons is poorly understood.

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