basement membrane disassembly

Definition

Target type: biologicalprocess

The controlled breakdown of the basement membrane in the context of a normal process such as imaginal disc eversion. [GOC:sart, PMID:17301221]

Basement membrane disassembly is a complex process involving the coordinated action of multiple enzymes and cellular components. It is essential for various physiological processes, including tissue remodeling, wound healing, and embryonic development.

The basement membrane, a specialized extracellular matrix, provides structural support and acts as a barrier between different tissues. It is composed of several key components, including collagen IV, laminin, nidogen, and perlecan.

During disassembly, the following steps occur:

1. **Activation of Matrix Metalloproteinases (MMPs):** MMPs are a family of zinc-dependent endopeptidases that degrade components of the extracellular matrix. Specific MMPs, such as MMP-2 and MMP-9, are known to degrade collagen IV and laminin, respectively.
2. **Cleavage of Basement Membrane Components:** Once activated, MMPs cleave the structural components of the basement membrane, disrupting its integrity. Collagen IV is broken down into smaller fragments, while laminin is cleaved at specific sites.
3. **Release of Growth Factors and Cytokines:** The degradation of the basement membrane releases various growth factors and cytokines, which can influence cell migration, proliferation, and differentiation.
4. **Cellular Adhesion and Migration:** The disruption of the basement membrane allows cells to detach and migrate through the ECM. This is crucial for processes like wound healing and embryonic development.
5. **Reorganization of the Basement Membrane:** As cells migrate, the basement membrane may undergo reorganization and repair. New ECM components can be synthesized and deposited, leading to the formation of a new basement membrane.

**Factors Regulating Basement Membrane Disassembly:**

- **Growth factors:** Several growth factors, including transforming growth factor-beta (TGF-beta) and fibroblast growth factor (FGF), can stimulate MMP expression and activate the disassembly process.
- **Cytokines:** Inflammatory cytokines like TNF-alpha and IL-1 can also induce basement membrane disassembly.
- **Mechanical forces:** Physical forces, such as stretching or compression, can trigger MMP activation and contribute to basement membrane disassembly.

**Disruption of Basement Membrane Disassembly:**

- **Abnormal basement membrane degradation:** Uncontrolled or excessive degradation of the basement membrane can lead to various diseases, including cancer metastasis and inflammatory diseases.
- **Defective basement membrane repair:** Impaired repair mechanisms can result in weakened basement membranes, leading to tissue fragility and dysfunction.

Overall, basement membrane disassembly is a tightly regulated process involving a delicate balance between degradation and repair. It is crucial for normal tissue function and plays a significant role in a variety of physiological and pathological processes.'
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Proteins (3)

Compounds (34)