Poster: Cell walls

Abs # 623: Characterization of dynamic alterations in cell wall architecture of maize by Fourier transform infrared and near infrared spectroscopy

Presenter:	Carpita, Nicholas C, carpita@purdue.edu
Authors	Carpita, Nicholas C (A)   Urbanowicz, Breeanna R (A)   Defernez, Marianne  (B)   Langewisch, Tiffany L (A)   Olek, Anna T (A)   Vermerris, Wilfred  (C)   Thomas, Steven R (D)   Koch, Karen  (E)   McCarty, Donald  (E)   McCann, Maureen C (F)
Affiliations:	(A): Department of Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-2054 (B): Department of Food Metrology, Institute of Food Research, Colney, Norwich NRA 7UA, United Kingdom (C): Departments of Agronomy and Agricultural & Biological Engineering, Purdue University, West Lafayette, IN 47907-2054 (D): National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 (E): Horticultural Sciences Department, University of Florida, Gainesville, FL 32611 (F): Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2054
Web Site:	http://www.btny.purdue.edu/faculty/carpita

Discriminant analyses of Fourier transform infrared (FTIR) and near infrared (NIR) spectra have been developed as high through-put methods to identify mutations affecting maize cell wall polysaccharide components and wall architecture. Maize lines carrying segregating sequence-tagged Mu-insertions introgressed into the inbred W22 genetic background were generated and used as primary material for mutation screens. Disrupted genes of mutants are identified based on the position of the insertional element. Reverse-genetics DNA grids representing nearly 20,000 lines are being developed to identify those with Mu elements located near cell-wall relevant genes of interest. These methods are employed to identify a broad range of mutants involved in the biogenesis and dynamic alteration of cell wall composition and architecture during growth and development of maize coleoptiles and field grown plants. In contrast to Arabidopsis, maize has type II cell walls, which are composed of cellulose microfibrils, glucuronoarabinoxylans (GAXs) of varying degrees of side-group substitution, and mixed-linkage (1,3),(1,4)-β-D-glucans (β-glucans) interwoven with a complex three-dimensional network of phenylpropanoids. Several discriminant analysis and class modeling algorithms were employed to identify characteristic spectral signatures permitting quantitation of cellulose, GAXs, β-glucan, phenylpropanoids, and the four major monosaccharides, arabinose, xylose, glucose and galactose. Supported by the NSF Plant Genome Research and REU programs