Getting nervous: the origins and evolution of NAP8

Neurulation is the embryological process which forms the precursors of the central nervous system and occurs after gastrulation has established the three primary cell layers of the embryo: ectoderm, mesoderm, and endoderm. In humans, the majority of this system is formed via primary neurulation, in which the central portion of the ectoderm—originally appearing as a flat sheet of cells—folds upwards and inwards, sealing off to form a hollow neural tube. As development proceeds, the...

The nervous system is one of the most complex systems in our body. It is organized into two main divisions: the central nervous system (CNS) and the peripheral nervous system (PNS).
The CNS, comprising the brain and spinal cord, houses billions of neurons. The brain is housed in the skull, while the spinal cord is linked to the brain through the foramen magnum of the occipital bone and is surrounded by the protective structure of the vertebral column. It is responsible for processing various...

In the CNS, neurogenesis, the birth of new neurons from stem cells, is limited to the hippocampus in adults. In other regions of the brain and spinal cord, neurogenesis is almost non-existent due to inhibitory influences from neuroglia, especially oligodendrocytes, and the absence of growth-stimulating cues. The myelin produced by oligodendrocytes in the CNS inhibits neuronal regeneration. Furthermore, astrocytes proliferate rapidly after neuronal damage, forming scar tissue that physically...

The nucleoid represents a structurally and functionally distinct region within prokaryotic cells, where the cell's DNA and associated proteins are housed. Unlike eukaryotic cells, prokaryotes lack a membrane-bound nucleus, and the nucleoid facilitates the organization and accessibility of the genetic material within this constraint. The DNA in most bacteria and archaea exists as a single, circular, double-stranded molecule that is highly compacted through supercoiling and interactions with...