Dear Students,

I'm very sorry but I'm currently having problems with video recording - I hope to solve the problem soon...in the meanwhile, please find here an introduction to the topic I propose you to work on this week.

In vertebrates, the complex structure of the central nervous system, with on one side the different brain areas characterized by their unique shape, cellular composition and connections and on the other side the spinal cord with its more conserved organized structure,  originates from an anatomically very simple structure which, as you well know... is the neural tube.

The understanding of the polarity and regional identity that give rise to the different parts of the nervous system has been at the core of developmental neurobiology research in the last 25 years.

It’s now clear that the pattern of the nervous system development is controlled by the occurrence of few antagonizing soluble factors, often acting as morphogens which influence the expression of specific transcription factors – the homeotic genes - that act as master genes regulating the expression of downstream target genes which are specific for the regional identity of the different areas of the nervous system.

By reading the instant notes on the start@unito platform you will find a synthesis of the main principles regulating polarity and regional identity in the CNS along both the antero-posterior and dorso-ventral axis.

You will see how the primary organizer, besides being crucial in neural induction also influences antero-posterior patterning, moreover, you will read about the role of secondary organizers in the anterior part of developing neural tube, namely, the anterior neural ridge, the zona limitans intrathalamica and the Istmic organizer (also known as the mid-hindbrain boundary), which are essential to define the positional identity of progenitors that will give rise to specific brain regions.