SUMMARY
Microtubules (MTs) are cytoskeletal polymers that undergo dynamic instability, the stochastic transition between growth and shrinkage phases. MT dynamics are required for diverse cellular processes, and, while intrinsic to tubulin, are highly regulated. However, little is known about how MT dynamics facilitate or are regulated by tissue biogenesis and differentiation. We imaged MT dynamics in a smooth muscle-like lineage in intact developing C. elegans. All aspects of MT dynamics change significantly as stem-like precursors exit mitosis and, secondarily, as they differentiate. We found that suppression but not enhancement of dynamics perturbs differentiated muscle function in vivo. Distinct ensembles of MT-associated proteins are specifically required for tissue biogenesis versus tissue function. A CLASP family MT stabilizer and the depolymerizing kinesin MCAK are differentially required for MT dynamics in the precursor or differentiated cells, respectively. All these multidimensional phenotypic comparisons were facilitated by a novel data display method, the diamond graph.