Elliot Meyerowitz and Christopher Somerville

USA - USA/Canada

2006 Balzan Prize for Plant Molecular Genetics

Research Project 

Live Imaging of Cellular Differentiation in Shoot Apical Meristems and in Cellulose Synthesis

Elliot Meyerowitz is George W. Beadle Professor of Biology and Investigator of the Howard Hughes Medical Institute at the California Institute of Technology’s Division of Biology. Christopher R. Somerville is Emeritus Professor of Energy Biosciences at the University of California, Berkeley.

Meyerowitz and Somerville developed a research project employing live imaging of dynamic plant processes followed by computational image processing to study two key processes: cellular differentiation in shoot apical meristems and cellulose synthesis. Elliot Meyerowitz initially involved Marcus Heisler, a pioneer of the new live imaging method, who worked on the live imaging of growing shoot apical meristems and computational modeling of cell behaviour and cell- cell communication during meristem growth. After Dr. Heisler left Caltech to establish his own laboratory at the European Molecular Biology Laboratory in Heidelberg, the project involved two additional postdoctoral fellows, Dr. Wuxing Li and Dr. Paul Tarr, who carried the shoot apical meristem work forward by investigating the involvement of the plant hormones auxin and cytokinin in the control of cell expansion, division and gene expression, and therefore, the contribution of these growth hormones to the interaction of physical and chemical signaling that controls meristem cell behaviour.

The work done in this part of the project led to a new National Institutes of Health grant on the action of hormones in the shoot apical meristem, which allowed the work to continue.

Professor Somerville involved three postdoctorate students in studies concerning the molecular mechanisms associated with the synthesis or depolymerization of cellulose. The research program in the Somerville laboratory focused on understanding several aspects of the control of cellulose synthesis or depolymerization. In 2013, postdoctoral fellow Patricia Bubner joined the Somerville groups following doctoral studies in Graz, Austria, and studied the role of glycosylation on enzyme activity by using genetic methods to modify the amount and location of glycans on proteins. Former postdoctoral fellow Ying Gu studied the role of the microtubule cytoskeleton in orienting the deposition of cellulose microfibrils by analyzing mutants in which the deposition is altered. Balzan funds were also used by Professor Somerville to support then postdoctoral fellow Seth DeBolt, who investigated the involvement of sterol glycosides in cellulose synthesis.

In December 2007, Professor Somerville moved his laboratory from Carnegie to the University of California, Berkeley. The project was inactive until the summer of 2009 due to administrative delays associated with moving the funds from one institution to another. Somerville’s Balzan funds have been used to partially support two graduate students, Adisorn Chaibang and Brad Dotson. Chaibang examined the role of two laccase enzymes in lignin biosynthesis and Dotson explored the function of a family of proteins of unknown function that appear to play important roles in cell wall biosynthesis.

Li W, Zhou Y, Liu X, Yu P, Cohen JD, Meyerowitz EM. 2013. LEAFY controls auxin response pathways in floral primordium formation. Science Signaling, 6(270), ra23.
Li S, Lei L, Somerville CR, Gu Y. 2012. Cellulose synthase interactive protein 1 (CSI1) links microtubules and cellulose synthase complexes. Proceedings of the National Academy of Science. 109 (1): 185-190.
Heisler MG, Hamant O, Krupinski P, Uyttewaal M, Ohno C, Jönsson H, Traas J, Meyerowitz EM. 2010. Alignment between PIN1 polarity and microtubule orientation in the shoot apical meristem reveals a tight coupling between morphogenesis and auxin transport. PLoS Biology 8, e1000516.
DeBolt S, Scheible WR, Schrick K, Auer M, Beisson F, Bischoff V, Bouvier-Navé P, Carroll A, Hematy K, Li Y, Milne J, Nair M, Schaller H, Zemla M, Somerville CR. 2009. Mutations in UDP-glucose: sterol glucosyltransferase in Arabidopsis cause transparent testa phenotype and suberization defect in seeds. Plant Physiology. 151: 78-87.
Gu Y, Deng Z, Paredez AR, DeBolt S, Wang Z, Somerville C. 2008. Prefoldin j6 is required for normal microtubule dynamics and organization in Arabidopsis. Proceedings of the National Academy of Science. 105 (46): 18064-18069.
Hamant O, Heisler MG, Jönsson H, Krupinski P, Uyttewaal M, Bokov P, Corson F, Sahlin P, Boudaoud A, Meyerowitz EM, Couder Y, Traas J. 2008. Developmental Patterning by Mechanical Signals in Arabidopsis. Science. Vol. 322, no. 5908: 1650-1655.

Excerpt from the: The Balzan Prizewinners’ Research Projects: An Overview 2018