Washington University in St. Louis
Campus Box 1137
One Brookings Drive
St. Louis, MO 63130-4899
The Dixit lab seeks to understand the mechanisms underlying plant cell morphogenesis. Our work focuses on the cortical microtubule cytoskeleton, which defines plant cell shape by serving as a scaffold for cell wall assembly. Our goal is to understand: 1) how cells create, maintain and remodel cortical microtubule arrays to dynamically control plant growth and development; and 2) how the cortical microtubule array orchestrates directional deposition of cell wall material. We are addressing these questions in the model plant Arabidopsis thaliana using a combination of molecular genetics, high resolution live-cell imaging and computer simulation studies. In addition, we are developing new techniques for reconstituting the dynamics and interactions of cortical microtubules in vitro to analyze the functions of key molecules under controlled conditions and at single molecule level. Current research areas in the lab are:
1. Identification and functional analyses of the Arabidopsis microtubule plus-end protein complex
2. Development of computer simulation models to quantitatively study cortical microtubule organization
3. Investigation of the function of kinesins in cell wall assembly
4. Characterization of the role of katanin and MAP65 proteins in microtubule organization
Zhu C, Ganguly A, Baskin TI, McClosky DD, Anderson CT, Foster C, Meunier KA, Okamoto R, Berg H and Dixit R (2015). The FRA1 kinesin contributes to cortical microtubule-mediated trafficking of cell wall components. Plant Physiology, 167: 780-792.
Zhang Q, Fishel EA, Bertroche T and Dixit R (2013). Microtubule severing at crossover sites by katanin generates ordered cortical microtubule arrays in Arabidopsis. Current Biology, 23: 2191-2195.
Ganguly A and Dixit R (2013). Mechanisms for regulation of plant kinesins. Current Opinion in Plant Biology, 16: 704-709.
Dixit R (2013). Plant cytoskeleton: DELLA connects gibberellins to microtubules. Current Biology, 23: R479-R481.
Fishel EA and Dixit R (2013). Role of nucleation in cortical microtubule array organization: variations on a theme. Plant Journal, 75: 270-277.
Tulin A, McClerklin S, Huang Y and Dixit R (2012). Single-molecule analysis of the microtubule crosslinking protein MAP65-1 reveals a molecular mechanism for contact-angle-dependent microtubule bundling. Biophysical Journal, 102: 802-809.
Zhu C and Dixit R (2012). Functions of the Arabidopsis kinesin superfamily of microtubule-based motor proteins. Protoplasma, 249:887-899.
Zhu C and Dixit R (2011). Single molecule analysis of the Arabidopsis FRA1 kinesin shows that it is a functional motor protein with unusually high processivity. Molecular Plant, 4: 879-885.
Sun F, Zhu C, Dixit R and Cavalli V (2011). Sunday Driver /JIP3 binds kinesin heavy chain directly and enhances its motility. EMBO Journal, 30:3416-3429.
Eren EC, Dixit R and Gautam N (2010) A three-dimensional computer simulation model reveals the mechanisms for self-organization of plant cortical microtubules into oblique arrays. Molecular Biology of the Cell, 21: 2674-2684.