From patterning signals to growth and back

As embryos develop, systemic signals, which convey hormonal and nutritional information, control the growth of its various tissues and organs. At the same time, local signals, sometimes called morphogens, are produced within each tissue to organise positional information, ensuring that various cell types are produced in the correct pattern. In well documented cases, these patterning signals have been found also to promote growth, perhaps allowing coordination between patterning and growth. These observations show that individual tissues must integrate local and systemic pro-growth signals. So far, relatively little is known about how morphogens promote growth.

We propose to first develop means of precisely controlling morphogen signal transduction using light or changes in temperature. This will enable us to identify the molecules that mediate the pro-growth activity of morphogens and to find out how this activity is coordinated with that of other pro-growth signals, local and systemic. We will also ask if known growth regulators affect morphogen signalling as this could explain the observation that patterns scale with tissue size.

Our experiments will uncover in molecular detail how various signals are integrated to ensure that tissues grow in a timely and proportionate manner.