Neuronal development is often regulated by the graded distribution of guidance molecules, which can either attract or repel the neuronal migration or neurite projection when presented in a format of concentration gradients, or chemotaxis.
A research team from City University of Hong Kong (CityU) has tackled this problem in a precise and systematic way by developing a new device, and has recently published their findings in a research article on the journal Nature Communications, titled "High-throughput three-dimensional chemotactic assays reveal steepness-dependent complexity in neuronal sensation to molecular gradients".
It is well known that the concentration gradients of guidance molecules, such as netrin or semaphorin (Sema) proteins, play critical roles in embryonic neural development.
Yet, how exactly the physical profiles of molecular gradients, e.g.
the changing rate of concentration profiles (gradient steepness), interplays with neuronal development has long remained an unanswered question.
Part of the reason was the lack of 3D devices that can recapitulate important features of brain tissues outside the human body.