Welcome to the Shaw Lab

TubulesThe Shaw laboratory studies how the microtubule cytoskeleton organizes into function array patterns that influence cellular morphogenesis. We use the Arabidopsis hypocotyl cell as a model system because of the relatively simple geometry and the established connection between specific microtubule array patterns and cell elongation.

The microtubules at the cell cortex act as guides for the deposition of cellulose microfibrils as they are made at the plasma membrane. The resulting pattern of cellulose fibers in the extracellular matrix influences the direction of cell wall expansion, and thus, cellular morphogenesis. Our primary focus is the discovery of mechanisms that organize the microtubules active in templating cellulose deposition. The laboratory uses advanced light microscopy techniques, genetics, computational modeling, and biochemistry to advance our knowledge in this area.Trajectory Maps

Cortical microtubules reposition themselves through polymer treadmilling, the addition of subunits at one end with loss of subunits at the other. Our recent investigations showing that treadmilling microtubules are nucleated into patterns with a common underlying architecture has dramatically reshaped the direction of our work. Using custom tracking and analysis methods, we are investigating how microtubules in this acentrosomal system are initially directed and determining the extent to which self-organization influences microtubule array pattern.

Plant cell morphogenesis requires the coordination of signals that tell the cell to expand with signals that tell the cytoskeleton how to organize. We are investigating the hormone reception pathways that induce growth and transverse cortical microtubule array patterning using genetics and cell biological methods. Development of new imaging and image analysis technology, combined with genetic tools, is providing exciting opportunity for studying how dynamic cytoskeletal assembly relates to anisotropic cell expansion.

Auxin Induction