Determining organ size through growth rate dependent negative feedback without sensing size.

Drosophila imaginal discs are the favoured system to study organ size determination. The intrinsic mechanism of organ size determination remains elusive despite decades of research into the cellular nature, mechanics and genetics of growth in the wing imaginal discs. Here we propose a new model whose basis is growth rate dependent-negative feedback without size being sensed. We show that alterations in size before the growth period are not corrected for, but alterations in growth rate during the start of the growth period induce size-restoring feedback.