Each cellular organelle carries out a distinct function, which is not only related to its molecular composition, but in many cases also to its size. …
While approaching near to complete proteomic parts lists of cellular structures and organelles, mechanisms that control their defined shape and size remain poorly understood. One reason why this question has been so hard to answer is that the size of an organelle is generally not simply set by a “ruler” but is an emergent property of molecular collectives.
“Emergence” describes the way complex properties and patterns of a system arise by numerous elements, which interact by relatively simple rules. Examples include the generation of an infinite variety of six-sided snowflakes from frozen water in snow. Similarly, “flocking”, the coordinated motion of animals observed in bird flocks, fish schools, or insects swarms, is considered an emergent behaviour. In physics emergent behaviours are commonly studied to describe complex systems. Physics thus provides a framework for relating the microscopic properties of individual molecules to the macroscopic properties of materials. This exactly is the key challenge in modern cell biology, bridging the gap between individual molecules and their collective behaviour. Therefore, my lab combines cell biological experiments, single molecule studies, and mathematical modelling to dissect the principles that underlay cellular scaling.