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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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P2X Receptors in The Post-Structure Era

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Dr. Rishabh Pathak

P2X receptors are a class of ligand-gated ion channels activated by extracellular ATP, playing crucial roles in various physiological and pathological processes in the nervous system. Here is an overview of P2X receptors in the post-structure era, focusing on recent advancements and implications:


1.      Structural Insights:

oInitial Discoveries: Early structural studies using X-ray crystallography and cryo-electron microscopy provided insights into the overall architecture of P2X receptors, revealing trimeric assembly and ligand-binding sites.

o  Recent Advances: High-resolution structures of P2X receptors, such as P2X3 and P2X7, have elucidated the conformational changes upon ATP binding, ion permeation pathways, and allosteric modulation sites.

2.     Functional Diversity:

o Subunit Composition: P2X receptors are composed of seven subunits (P2X1-7), each exhibiting distinct pharmacological properties, ion selectivity, and expression patterns in different cell types.

o Functional Roles: P2X receptors mediate fast excitatory neurotransmission, synaptic plasticity, pain sensation, immune responses, and neuroinflammation, highlighting their diverse functions in health and disease.

3.     Allosteric Modulation:

o Allosteric Sites: Recent studies have identified allosteric modulatory sites on P2X receptors that can fine-tune channel activity, providing opportunities for developing subtype-selective modulators with therapeutic potential.

o Pharmacological Targeting: Allosteric modulators of P2X receptors offer novel strategies for modulating receptor function, potentially avoiding the limitations of orthosteric ligands and enhancing therapeutic specificity.

4.    Pathophysiological Implications:

o Neurological Disorders: Dysregulation of P2X receptors is implicated in neurological disorders such as chronic pain, migraine, epilepsy, and neurodegenerative diseases, making them attractive targets for drug development.

o    Immune Responses: P2X receptors play critical roles in immune cell activation, inflammation, and cytokine release, suggesting their involvement in immune-related pathologies and potential immunomodulatory interventions.

5.     Therapeutic Potential:

o Drug Development: Targeting P2X receptors with selective agonists, antagonists, or allosteric modulators holds promise for developing novel therapeutics for pain management, neuroprotection, and inflammatory conditions.

o    Precision Medicine: Understanding the structural and functional diversity of P2X receptors enables the design of personalized treatment strategies tailored to specific receptor subtypes and disease contexts.

In the post-structure era, advances in understanding the structural basis, functional diversity, allosteric modulation, and pathophysiological implications of P2X receptors have opened new avenues for exploring their roles in health and disease. Harnessing the therapeutic potential of P2X receptors through precise modulation and targeted drug development offers exciting opportunities for advancing neuropharmacology and personalized medicine.

 

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