anterior neural tube closure

Definition

Target type: biologicalprocess

The step in the formation of the neural tube, where the paired anterior neural folds are brought together and fuse at the dorsal midline. [GOC:BHF, GOC:dph, GOC:hal, PMID:17286298]

Anterior neural tube closure is a crucial developmental process that occurs during the early stages of embryonic development. It involves the coordinated fusion of the neural folds, which are two ridges of ectoderm that form along the dorsal midline of the embryo. This fusion results in the formation of the neural tube, which will ultimately give rise to the brain and spinal cord.

The process of anterior neural tube closure begins at the midbrain level and proceeds in a rostral-caudal direction. It involves several key steps:

1. **Neural fold elevation:** The neural folds, which are thickened regions of ectoderm, begin to elevate and approach each other at the midline. This elevation is driven by changes in cell shape and adhesion, as well as by the action of specific signaling molecules.

2. **Apical constriction:** At the apex of each neural fold, the cells undergo apical constriction, which is a process of narrowing at the apical surface of the cells. This constriction pulls the neural folds closer together.

3. **Cell adhesion and fusion:** As the neural folds come into contact, the cells at their apices adhere to each other through cell-cell junctions. This adhesion is mediated by specific cell adhesion molecules (CAMs), such as cadherins. Once adhered, the cells undergo fusion, forming a continuous neural tube.

4. **Closure of the neural pore:** As the neural folds fuse, a small opening, called the neural pore, remains at the anterior end of the tube. This pore eventually closes as the neural folds continue to fuse.

5. **Formation of the neural crest:** At the dorsal edge of the closing neural folds, a population of cells known as the neural crest cells delaminate and migrate away from the neural tube. These cells will give rise to a variety of structures, including the peripheral nervous system, melanocytes, and cartilage.

The proper closure of the anterior neural tube is essential for the development of a healthy brain and spinal cord. Failure of anterior neural tube closure can lead to severe birth defects, such as anencephaly (absence of the brain) and spina bifida (defects in the spinal cord).

These defects are caused by a variety of factors, including genetic mutations, nutritional deficiencies, and exposure to teratogens (environmental toxins). Understanding the molecular and cellular mechanisms underlying anterior neural tube closure is crucial for developing strategies to prevent and treat these birth defects.'
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Proteins (2)

Compounds (29)