PT  - JOURNAL ARTICLE
AU  - XinXin Du
AU  - Lucy Erin O’Brien
AU  - Ingmar Riedel-Kruse
TI  - A model for adult organ resizing demonstrates stem cell scaling through a tunable commitment rate
AID  - 10.1101/137638
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 137638
4099  - http://biorxiv.org/content/early/2017/05/13/137638.short
4100  - http://biorxiv.org/content/early/2017/05/13/137638.full
AB  - Many adult organs grow or shrink to accommodate different physiological demands. Often, as total cell number changes, stem cell number changes proportionally in a phenomenon called ‘stem cell scaling’. The cellular behaviors that give rise to scaling are unknown. Here we study two complementary theoretical models of the adult Drosophila midgut, a stem cell-based organ with known resizing dynamics. First, we derive a differential equations model of midgut resizing and show that the in vivo kinetics of growth can be recapitulated if the rate of fate commitment depends on the tissue’s stem cell proportion. Second, we develop a twodimensional simulation of the midgut and find that proportion-dependent commitment rate and stem cell scaling can arise phenomenologically from the stem cells’ exploration of physical tissue space during its lifetime. Together, these models provide a biophysical understanding of how stem cell scaling is maintained during organ growth and shrinkage.