Dr. Marcos Nahmad, Centre for Research and Advanced Studies (Cinvestav)
Abstract: Organ growth is an exponential process driven mainly by cell proliferation, and therefore, even small variations in cell proliferation rates, when integrated over a relatively long time, will lead to large differences in size. How organs robustly control their final size despite perturbations in cell growth and cell proliferation rates is a fundamental question in developmental biology. Here we use a mathematical model to propose that in the developing wing of Drosophila, cell recruitment, a process in which undifferentiated neighbouring cells are incorporated into the wing primordium, determines the time in which growth is arrested in this system. Our model shows that perturbations in proliferation rates of wing-committed cells are compensated by an inversely proportional duration of growth. This mechanism ensures that the final size of the wing is robust in a range of cell proliferation rates. Furthermore, we predict that growth control is lost when fluctuations in cell proliferation affects both wing-committed and recruitable cells. Our model suggests that cell recruitment may act as a temporal controller of growth to buffer fluctuations in cell proliferation rates.
Bio: Dr. Marcos Nahmad’s lab works on the fundamental question of how global (organ-level) information is perceived and interpreted at the local (cellular level) during organ development and growth. To address these problems he uses tools from genetics, quantitative data analysis, image processing, and mathematical modeling of biological systems. In addition, he is deeply interested in science education and promotes active learning of STEM. He is the founder and organizer of the Science Teaching Workshop and frequently offers workshops on active learning for science teachers. Currently, he coordinates the Masters of Science and PhD programs in the Department of Physiology, Biophysics and Neurosciences at Cinvestav, and teaches at the Medical School of Universidad Anáhuac - Mexico.