Abstract Cells in living tissues are exposed to substantial mechanical forces and constraints imposed by neighboring cells, the extracellular matrix, and external factors. Mechanical forces and physical confinement can drive various cellular responses, including changes in gene expression, cell growth, differentiation, and migration, all of which have important implications in physiological and pathological processes, such as immune cell migration or cancer metastasis. Previous studies have shown that nuclear deformation induced by 3D confinement promotes cell contractility but can also cause DNA damage and changes in chromatin organization, thereby motivating further studies in nuclear mechanobiology. In this protocol, we present a custom‐developed, easy‐to‐use, robust, and low‐cost approach to induce precisely defined physical confinement on cells using agarose pads with micropillars and externally applied weights. We validated the device by confirming nuclear deformation, changes in nuclear area, and cell viability after confinement. The device is suitable for short‐ and long‐term confinement studies and compatible with imaging of both live and fixed samples, thus presenting a versatile approach to studying the impact of 3D cell confinement and nuclear deformation on cellular function. This article contains detailed protocols for the fabrication and use of the confinement device, including live cell imaging and labeling of fixed cells for subsequent analysis. These protocols can be amended for specific applications. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Design and fabrication of the confinement device wafer Basic Protocol 2: Cell confinement assay Support Protocol 1: Fixation and staining of cells after confinement Support protocol 2: Live/dead staining of cells during confinement
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Creating Optimal Western Blot Conditions for OPA1 Isoforms in Skeletal Muscle Cells and Tissue
Abstract OPA1 is a dynamin‐related GTPase that modulates mitochondrial dynamics and cristae integrity. Humans carry eight different isoforms of OPA1 and mice carry five, all of which are expressed as short‐ or long‐form isoforms. These isoforms contribute to OPA1's ability to control mitochondrial energetics and DNA maintenance. However, western blot isolation of all long and short isoforms of OPA1 can be difficult. To address this issue, we developed an optimized western blot protocol based on improving running time to isolate five different isoforms of OPA1 in mouse cells and tissues. This protocol can be applied to study changes in mitochondrial structure and function. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Western Blot Protocol for Isolating OPA1 Isoforms in Mouse Primary Skeletal Muscle Cells
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- PAR ID:
- 10593289
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- PubMed
- Date Published:
- Journal Name:
- Current Protocols
- Volume:
- 5
- Issue:
- 2
- ISSN:
- 2691-1299
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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