© 2004 Oxford University Press
The Relation of Starch Phosphorylases to Starch Metabolism in Wheat
Institute of Plant Physiology, University of Bayreuth, 95440 Bayreuth, Germany
Tissues of wheat (Triticum aestivum L., var. Star) exhibit three starch phosphorylase activity forms resolved by non-denaturing polyacrylamide gel affinity electrophoresis (P1, P2 and P3). Compartmentation analysis of young leaf tissues showed that P3 is plastidic, whereas P1 and P2 are cytosolic. P1 exhibits a strong binding affinity to immobilized glycogen upon electrophoresis, whereas P2 and the chloroplastic P3 do not. Cytosolic leaf phosphorylase was purified to homogeneity by affinity chromatography. The single polypeptide product constituted both the P1 and P2 activity forms. Probes for the detection of phosphorylase transcripts were derived from cDNA sequences of cytosolic and plastidic phosphorylases, and thesetogether with activity assays and a cytosolic phosphorylase-specific antiserumwere used to monitor phosphorylase expression in leaves and seeds. Mature leaves contained only plastidic phosphorylase, which was also strongly evident in the endosperm of developing seeds at the onset of reserve starch accumulation. Germinating seeds contained only cytosolic phosphorylase, which was restricted to the embryo. Plastidic phosphorylase thus appears to be associated with transitory leaf starch metabolism and with the initiation of seed endosperm reserve starch accumulation, but it plays no role in the degradation of the reserve starch. Cytosolic phosphorylase may be involved in the processing of incoming carbohydrate during rapid tissue growth.
1 Corresponding author: Present address: Institute of Toxicology, University of Würzburg, Versbacher Strasse 9, 97078 Würzburg, Germany; E-mail, Nicole.Schupp{at}toxi.uni-wuerzburg.de.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
V. V. Radchuk, L. Borisjuk, N. Sreenivasulu, K. Merx, H.-P. Mock, H. Rolletschek, U. Wobus, and W. Weschke Spatiotemporal Profiling of Starch Biosynthesis and Degradation in the Developing Barley Grain Plant Physiology, May 1, 2009; 150(1): 190 - 204. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Grimaud, H. Rogniaux, M. G. James, A. M. Myers, and V. Planchot Proteome and phosphoproteome analysis of starch granule-associated proteins from normal maize and mutants affected in starch biosynthesis J. Exp. Bot., September 1, 2008; 59(12): 3395 - 3406. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Satoh, K. Shibahara, T. Tokunaga, A. Nishi, M. Tasaki, S.-K. Hwang, T. W. Okita, N. Kaneko, N. Fujita, M. Yoshida, et al. Mutation of the Plastidial {alpha}-Glucan Phosphorylase Gene in Rice Affects the Synthesis and Structure of Starch in the Endosperm PLANT CELL, July 1, 2008; 20(7): 1833 - 1849. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Lorenzo-Morales, J. Kliescikova, E. Martinez-Carretero, L. M. De Pablos, B. Profotova, E. Nohynkova, A. Osuna, and B. Valladares Glycogen Phosphorylase in Acanthamoeba spp.: Determining the Role of the Enzyme during the Encystment Process Using RNA Interference Eukaryot. Cell, March 1, 2008; 7(3): 509 - 517. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Lu, J. M. Steichen, J. Yao, and T. D. Sharkey The Role of Cytosolic {alpha}-Glucan Phosphorylase in Maltose Metabolism and the Comparison of Amylomaltase in Arabidopsis and Escherichia coli Plant Physiology, November 1, 2006; 142(3): 878 - 889. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Alonso-Casajus, D. Dauvillee, A. M. Viale, F. J. Munoz, E. Baroja-Fernandez, M. T. Moran-Zorzano, G. Eydallin, S. Ball, and J. Pozueta-Romero Glycogen Phosphorylase, the Product of the glgP Gene, Catalyzes Glycogen Breakdown by Removing Glucose Units from the Nonreducing Ends in Escherichia coli. J. Bacteriol., July 1, 2006; 188(14): 5266 - 5272. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Lu, J. P. Gehan, and T. D. Sharkey Daylength and Circadian Effects on Starch Degradation and Maltose Metabolism Plant Physiology, August 1, 2005; 138(4): 2280 - 2291. [Abstract] [Full Text] [PDF] |
||||




