25 June 2018

DanStem Seminar by Ditte Andersen and Julien Colombani


Ditte Andersen and Julien Colombani, Institut Valrose, Nice, France Title: Drosophila as a model for studying inter-organ communication and intestinal stem cell physiology

Ditte Andersen and Julien Colombani, Institut Valrose, Nice, France

27 June 2018, 12:15

Holst Auditorium

Animal growth is a complex process that is intimately linked to the developmental program in order to form adults with proper size and proportions. Genetics is an important determinant of growth, as exemplified by the role of local diffusible molecules in setting organ proportion in a given specie. In addition to this genetic control, organisms use adaptative responses allowing modulating the size of individuals according to environmental cues, among which nutrition. Therefore, a sophisticated crosstalk between local and global cues is at play for the ultimate determination of the size of an individual.

Distinct hormone axes controls the two main parameters that determine final adult size, i.e. the speed of growth, or growth rate, and the duration of growth, which in many species is limited by sexual maturation. In metazoans, the insulin/insulin-like growth factor (IGF) signaling pathway (IIS) controls the growth rate of tissues according to nutrient availability. On the other hand, the clock that runs the developmental transitions and determines the duration of growth is controlled by steroid hormone regulations. Again, important cross-talks exist between these regulations. Our approach to understand this complex orchestration is to utilize the power of a simple genetic metazoan model like Drosophila melanogaster .