Biochemistry

Bruce A. McClure

Professor of Biochemistry

E-mail:mcclureb@missouri.edu

Office: 112 Schweitzer Hall

Mail: Biochemistry
117 Schweitzer Hall
University of Missouri
Columbia, MO 65211

Phone: 573-882-3932

Fax: 573-882-5635

Lab: 573-882-3939

Educational background

Notable honors and service

• Fellow, American Association for the Advancement of Science
• Board of Directors, Science Teachers of Missouri, 2008-2009
• Program Director for Plant, Fungal and Microbial Development at the US National Science Foundation (2010-2012)

Research summary

Researchers in the McClure Lab investigate the molecular basis of pollen recognition.

Research description

Research in the McClure lab is focused on understanding how pollen pistil communication controls plant mating. We study S-RNase-based self-incompatibility in Nicotiana and interspecific pollen recognition and rejection between tomato and its wild relatives. The genus Nicotiana is useful because of its ease of experimental manipulation, and the inter- and intra-specific compatibility relationships are well known. For example, N. alata displays gametophytic self-incompatibility (SI). Self-pollen and pollen from closely related plants are rejected, thus maintaining hybrid vigor. N. alata also has specific mechanisms for recognizing and rejecting pollen from related species such as N. plumbaginifolia and N. tabacum. Likewise, tomato, Solanum lycopersicum (formerly Lycopersicon esculentum), also has well defined crossing relationships with its wild relatives such as SI S. habrochaities and SI S. pennellii. In addition there are many powerful genetic tools available for studies of tomato.

We use genetic and biochemical techniques to identify factors that contribute to inter- and intra-specific pollen recognition and rejection. A theme for pollen-pistil interactions is that the pistil secretes factors into the extracellular matrix that pollen tubes use as a guide to the ovary. Our challenge is to identify these factors and the pollen factors they interact with to control mating. In SI for example, the pistil produces potentially cytotoxic proteins called S-RNases that are taken up by growing pollen tubes. When pollen is rejected, S-RNase is released into the pollen tube cytoplasm and growth is inhibited. Thus, our research involves biochemical and genetic experiments to identify critical pollen and pistil proteins and cell biological experiments to determine how their cellular context contributes to their functions. By understanding the natural systems control pollination, plant breeders can design new strategies to manipulate their breeding behavior for their own purposes.

Selected publications:

Jime´nez-Dura´n, K., McClure, B., García-Campusano, F., Rodríguez-Sotres, R., Cisneros, J., Busot G.Y., and Cruz-Garcı´a F.* (2013) NaStEP: a proteinase inhibitor essential to self-incompatibility and a positive regulator of the HT-B stability in Nicotiana pollen tubes. Plant Physiol. 161:97-107.  doi:10.1104/pp.112.198440 *Corresponding author.

Chalivendra^, S.C., Lopez-Casado, G., Kumar, A., Kassenbrock, A.R., Royer, S., Covey, P.A., Dempsey, L., Stack, S.M., Rose, J.K.C., McClure, B. and Bedinger, P.A.* (2013) Developmental onset of reproductive barriers and associated proteome changes in stigma/styles of Solanum pennellii.  J. Exp. Bot.  64:265-279 *Corresponding author.

McClure B. (2012) Plant self-incompatibility: Ancient system becomes a new tool. Curr. Biol.  22:R86-87. doi: 10.1016/j.cub.2011.12.034

Rebello C.M.*, Siegel M.A., Witzig S., Freyermuth S.K., McClure B. (2012) Epistemic beliefs and conceptual understanding in biotechnology: A case study. Res. Sci. Educ. 42(2):353-371 DOI 10.1007/s11165-010-9201-6. *Corresponding author.

McClure B., Cruz-Garcia, F., Romero, C. (2011) Compatibility and incompatibility in S-RNase-based systems. Ann. Bot.  108:647-658. doi: 10.1093/aob/mcr179

Bedinger, P.*, Chetelat, R., McClure, B., Moyle, L., Rose, J., Stack, S., van der Knaap, E., Baek, Y-S., Lopez-Casado, G., Covey, P., Kumar, A., Li, W., Nunez, R., Cruz-Garcia, F., Royer, S. (2010) Interspecific reproductive barriers in the tomato clade: opportunities to decipher mechanisms of reproductive isolation.  Sex. Plant Reprod. 24:171-187. *Corresponding author.

Covey P.A., Kondo K., Welch L., Frank E., Kumar A., Van der Knaap E., Nunez R., Lopez-Casado G., Rose J.K.C., McClure B.A., Bedinger P.A.* (2010) Multiple features that distinguish unilateral incongruity and self-incompatibility in the tomato clade. Plant J. 64: 367–378

McClure B. (2009) Darwin’s foundation for investigating self-incompatibility and the progress toward a physiological model for S-RNase-based SI. J. Exp. Bot. 60:1069-1081 doi:10.1093/jxb/erp024.

Lee C.B., Kim S., and McClure B. (2009) A pollen protein, NaPCCP, that binds pistil arabinogalactan proteins also binds phosphatidylinositol 3-phosphate and associates with the pollen tube endomembrane system. Plant Physiol. 149: 791-802 doi:10.1104/pp.108.127936

Busot G.Y., McClure B., Ibarra-Sánchez C.P., Jiménez-Durán K., Vázquez-Santana S., and Cruz-García F. (2008) Pollination in Nicotiana alata stimulates synthesis and transfer to the stigmatic surface of NaStEP, a vacuolar Kunitz proteinase inhibitor homologue. J. Exp. Bot. 2008 59:3187-3201 doi:10.1093/jxb/ern175

Lee C.B., Swatek K. N., and McClure B.A. (2008) Pollen proteins bind to the C-terminal domain of Nicotiana alata pistil arabinogalactan proteins. J. Biol. Chem. 283:26965-26973 doi:10.1074/jbc.M804410200

Lee C.B., Page L.E., McClure B.A., and Holtsford T.P. (2008) Postpollination hybridization barriers in Nicotiana Section Alatae. Sex. Plant Reprod. 21:183-195. doi 10.1007/s00497-008-0077-9

Kondo K., McClure B. (2008) New microsome-associated HT-family proteins from Nicotiana respond to pollination and define an HT/NOD-24 protein family. Mol. Plant 1: 634-644; doi:10.1093/mp/ssn018

Employment opportunities

Graduate students and postdoctoral candidates able to compete for funding are encouraged to apply.

Research areas: Cell-cell interactions in pollen recognition and rejection.

How to apply:

Electronic submission is required, e-mail to mcclureb@missouri.edu