b'Deciphering How Plants Grow34The Ehrhardt lab members are, from left to right: Jelmer Lindeboom, Jacob Moe-Lange, Sury Jha, Mackenzie Machado, Renate Weizbauer, and David Ehrhardt. Heather Meyer is not pictured. Image courtesy David Ehrhardt, Carnegie Institution for Science P lant cell growth and shape is determined byThey then asked how, after katanin cutting, the plus the extension of their cell walls. To directends stabilize to promote microtubule generation. cell wall construction and growth, plantThe team identified the protein CLASP as a potent cells have a highly organized interior scaffoldingstabilizer of these new plus ends. This research called a microtubule cytoskeleton. Environmentalprovides new avenues for engineering how plants signals, including light, reorganize this scaffold torespond to environmental changes and advances make growth responsive to environmental changes.our understanding of how similar cytoskeleton Carnegies David Ehrhardt and team discoveredmechanisms may work in animal cells, including those that this reorganization is driven by creating newin humans. microtubules by an unexpected process where the protein katanin severs the microtubules where theyMicrotubule plus ends switch from slowly growing to intersect, creating new plus ends that regrow.rapidly shrinking. The growing ends are stabilized by'