2007 Sectional Meeting Registration Form

Registration Deadline, March 15, 2007. To register, fill out the form below. Checks for registration fees can be made out to: American Society of Plant Biology, Midwest Section. We cannot accept credit card payments. Registration fees can be paid at the meeting or mailed to:

Chris Wolverton
Dept of Botany & Microbiology
90 S. Henry St.
Ohio Wesleyan University
Delaware, OH 43015

Send abstracts to: Susanne Hoffmann-Benning, hoffma16@msu.edu - Deadline March 1st (example abstract format below)

EXAMPLE ABSTRACT FORMAT

The Lethal Leaf-Spot 1 (LLS1) Protein Catalyzes Chlorophyll Degradation and is Localized to the Inner Chloroplast Membrane
Yang, Manli1 ,Wardzala, Ellen1, Haller, Steve1, Johal, Gurmukh S.2, Reinbothe, Steffen3, and Gray, John1. 1Dept. of Biology, University of Toledo, OH 43606, 2Plant Pathology Dept., Purdue University, IN 47906, 3Laboratoire de Genetique Moleculaire des Plantes, Universite Joseph Fourier et CNRS, Grenoble, France. (jgray5@uoft02.utoledo.edu).

The LLS1 protein provides an important protection against light-dependent cell death in higher plants. A functional genomics approach has now revealed that the Lls1 gene encodes pheophorbide a oxygenase (PaO) which catalyzes a key step in chlorophyll degradation (Pruzinská et al, 2003). We show that this gene function is conserved between monocots and dicots by direct complementation of the (accelerated cell death 1) mutation of Arabidopsis using the maize Lls1 cDNA (Yang et al, 2004, Plant Mol. Biol, In Press). We provide cellular subfractionation, chloroplast uptake, and in vivo, GFP reporter evidence to show that the LLS1 protein is localized to the inner membrane of the chloroplast in both monocots and dicots. We further show that the LLS1 protein is present in many plant species including lower plants such as moss and ferns. A bioinformatics survey revealed that Lls1 homologues exist in algae (Chlamydomonas) and cyanobacteria (Synechocystis, Anabaena and Trichodesmium) but not in the anoxygenic bacterium Chlorobium (Gray et al, 2004). Although the LLS1(PAO) protein is always present in photosynthetic tissues expression of the Lls1 gene increases following wounding. We interpret these findings to indicate that failure to remove pheophorbide a in lls1 plants results in the accumulation of a highly phototoxic chlorophyll intermediate near chloroplast membranes. Photoactivation of this intermediate results in damage to these membranes and loss of chloroplast integrity leading to the light-dependent cell death phenotype. Interestingly, the LLS1(PAO) protein is also found in all etiolated and non-photosynthetic tissues that we tested so it appears that the ability to degrade chlorophyll is a contingent metabolic activity present in all plant cells (Yang et al, 2004).