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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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Split-CRE Mediated Analysis of a Progenitor Cell Population Activated by Brain Lesions

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Dr. Rishabh Pathak

Split-Cre mediated analysis of a progenitor cell population activated by brain lesions involves a sophisticated genetic approach to track and manipulate specific cell populations in response to injury. Here are some key points related to Split-Cre mediated analysis of progenitor cells activated by brain lesions:

1.      Principle of Split-Cre System:

o Split-Cre Recombinase: The Split-Cre system involves dividing the Cre recombinase enzyme into two inactive fragments that can reconstitute functional Cre activity when brought together in proximity, allowing for spatial and temporal control over genetic recombination events.

o Cell-Specific Activation: By expressing one Cre fragment under the control of a cell type-specific promoter and the complementary fragment in response to injury signals or lesion-induced factors, the Split-Cre system enables the selective activation of Cre recombinase activity in the targeted progenitor cell population following brain lesions.

2.     Analysis of Activated Progenitor Cells:

oLineage Tracing: Upon reconstitution of functional Cre recombinase activity in response to brain lesions, the activated progenitor cells can be lineage-traced using Cre reporter alleles or genetic indicators to track their fate, differentiation potential, and contribution to tissue repair.

oCell Fate Determination: The Split-Cre system allows for the precise labeling and genetic manipulation of the progenitor cell population activated by brain lesions, facilitating the investigation of their fate decisions, lineage relationships, and regenerative capacity in the injured brain microenvironment.

3.     Temporal Control and Inducibility:

oTemporal Regulation: The Split-Cre system can incorporate inducible promoters or regulatory elements to control the timing of Cre reconstitution, enabling researchers to activate genetic labeling specifically in response to brain lesions at desired time points during the injury response.

oDynamic Analysis: Temporal control over Split-Cre mediated activation of progenitor cells allows for dynamic analysis of the cellular response to brain lesions, including the kinetics of progenitor cell activation, proliferation, migration, and differentiation in the context of injury-induced neurogenesis or gliogenesis.

4.    Functional Studies and Manipulations:

oGenetic Manipulations: The Split-Cre system can be coupled with genetic tools for conditional gene knockout, overexpression, or lineage-specific perturbations to investigate the functional role of the activated progenitor cell population in brain repair processes following lesions.

oBehavioral and Functional Assessments: By combining Split-Cre-mediated lineage tracing with behavioral assays, electrophysiological recordings, or imaging techniques, researchers can assess the functional integration of activated progenitor cells into the injured brain circuitry and their impact on neurological recovery.

In summary, Split-Cre mediated analysis of a progenitor cell population activated by brain lesions offers a powerful genetic strategy to selectively target, label, and manipulate specific cell populations in response to injury, providing insights into the regenerative potential, fate determination, and functional contributions of activated progenitor cells in the context of brain repair and recovery following neural damage.

 

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