Cell maturity gradient determines light regulated accumulation of proteins in pearl millet leaves

Research Article


Developing pearl millet leaves possess cells of increasing maturity from the leaf base to the tip with oldest cells at the leaf tip. This natural developmental gradient was used to analyze the photoregulation of enzymes located in cytosolic, peroxisomal, and plastidic compartments of the leaf in relation to the cell age. In dark-grown leaves, the level of plastidic protochlorophyllide oxidoreductase A (PORA) (EC protein increased from the leaf base to tip. Exposure to light reduced the level of PORA protein and stiumulated accmulation of PORB protein with increasing level from the base to the leaf tip. Light induced formation of cytosolic PEP carboxylase (EC in the leaf with induction being maximal in the leaf tip. The levels of peroxisomal protein catalase (EC showed gradual increase from the base to leaf tip in dark and light-grown leaves. By contrast, the distribution profile of cytosolic enzyme peroxidase (EC followed reverse pattern in the dark-and light-grown leaves. In dark-grown leaves, peroxidase level showed increase towards the leaf tip, whereas light exposure lowered peroxidase level near the leaf tip and stimulated near the leaf base. These results indicate that the cell maturity gradient in cooperation with plastids modulates in a dual fashion the magnitude and pattern of photoregulation of protein levels in pearl millet leaves. It promotes the level of proteins functionally related to plastids towards the leaf tip and at the same time suppresses the level of cytosolic proteins, restricting them to the leaf base.

Key words

Protochlorophyllide oxidoreductase Peroxidase Catalase Pennisetum americanum Cell maturity gradient PEP carboxylase 



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protochlorophyllide oxidoreductase




  1. Acevedo, A., Williamson, J.D., and Scandalios J.G. (1991) Photoregulation of Cat2 and Cat3 catalase genes in pigmented and pigment deficient maize: the circadian regulation of Cat3 is superimposed on its quasiconstitutive expression in maize leaves. Genetics 127: 601–607.PubMedGoogle Scholar
  2. Bajracharya D., Bergfeld R., Hatzfeld W-D., Klein S. and Schopfer P. (1987) Regulatory involvement of plastids in the development of peroxisomal enzymes in the cotyledons of mustard (Sinapsis alba L.) seedlings, J Plant Physiol 126: 421–436.Google Scholar
  3. Baker N.R. and Leech R.M. (1977) Development of photosystem I and photosystem II activities in leaves of light grown maize (Zea mays). Plant Physiol. 60: 640–644.PubMedGoogle Scholar
  4. Chollet R., Vidal J. and O’Leary M.H. (1996) Phosphoenolpyruvate carboylase: A ubiquitous, highly regulated enzyme in plants. Annu. Rev. Plant Physio. Plant Mol. Biol. 47: 273–298.CrossRefGoogle Scholar
  5. Datta R. and Sharma R. (1999) Temporal and spatial regulation of nitrate reductase and nitrite reductase in greening maize leaves. Plant Science 144: 77–83.CrossRefGoogle Scholar
  6. Datta R., Vally K.J.M. and Sharma R. (1999) Sugar mimics the light-mediated β-amylase induction and distribution in maize and pearl millet leaves. J. Plant Physiol. 154: 665–672.Google Scholar
  7. Davis B. (1964) Disc electrophoresis. II. Methods and application to human serum proteins. Ann. NY Acad. Sci. 121: 404–427.PubMedCrossRefGoogle Scholar
  8. Dean C. and Leech R.M. (1982) Genome expression during normal leaf development. I. Cellular and chloroplast numbers and DNA, RNA and protein levels in tissues of different ages within seven day old wheat leaf. Plant Physiol. 69: 904–910.PubMedCrossRefGoogle Scholar
  9. Griffiths W.T. (1991) Protochlorophyllide Photoreduction, in: Scheer H., (Ed), Chlorophylls. CRC Press, Boca Raton, pp. 433–450.Google Scholar
  10. Holtorf H., Reinbothe S., Reinbothe C., Bereza B. and Apel K. (1995) Two routes of chlorophyllide synthesis that are differentially regulated by light in barley (Hordeum vulgare L.). Proc. Natl. Acad. Sci. USA 92: 3254–3258.PubMedCrossRefGoogle Scholar
  11. John P.C.L., Sek F.J., Carmichael J.P. and McCurdy D.W. (1990) P34cdc2 homologue level, cell division, phytochrome responsiveness and cell differentiation in wheat leaves. J. Cell Sci. 97: 627–630.PubMedGoogle Scholar
  12. Kemp D.R. (1980) The location and site of the extension zone of emerging wheat leaves. New Phytol. 84: 729–737.CrossRefGoogle Scholar
  13. Laemmli U.K. (1970) Cleavage of structural proteins during the assembly of head of bacteriophage T4. Nature 222: 680–685.CrossRefGoogle Scholar
  14. Liaaen-Jensen S. and Jensen A. (1971) Quantitative determination of carotenoids in photosynthetic tissues, Meths. Enzymol. 235: 86–602.Google Scholar
  15. Lowry O.H., Rosenbrough N.J., Farr A.H. and Randall G.J. (1951) Protein measurement with folin-phenol reagent, J. Biol. Chem. 193: 256–275.Google Scholar
  16. Nelson T. and Langdale J.A. (1992) Developmental genetics of C4 photosynthesis. Ann. Rev. Plant Physio. Plant Mol. Biol. 43: 25–47CrossRefGoogle Scholar
  17. Poethig R.S. (1984) Cellular parameters of leaf morphogenesis in maize and tobacco. in: White R.A., Dickson W.C., (Eds), Contemporary problems in plant anatomy, Academic Press, New York, pp. 235–239.Google Scholar
  18. Reinbothe S., Reinbothe C., Holtorf H. and Apel K., (1995) Two NADPH: Protochlorophyllilde oxidoreductase in barley: Evidence for the selective disappearance of POR A during the light induced greening of etiolated seedlings. Plant Cell 7: 1933–1940.PubMedCrossRefGoogle Scholar
  19. Rodermel S. (2001) Pathways of plastid-to-nucleus signaling. Trends Plant Sci. 6: 471–478.PubMedCrossRefGoogle Scholar
  20. Sharma R., Sopory S.K. and Guha-Mukherjee S. (1979) Phytochrome regulation of peroxidase activities in maize III. Age dependence and subcellular localization. Z. Pflanzenphysiol. 94: 371–375.Google Scholar
  21. Sylvester A.W., Cande W.L. and Freeling M., (1990) Division and differentiation during normal and liguleless-1 in maize leaf development. Development 110: 985–1000.PubMedGoogle Scholar
  22. Thompson P., Bowsher C.G. and Tobin A.K., (1998) Heterogeneity of Mitochondrial Protein Biogenesis during Primary Leaf Development in Barley. Plant Physiol. 118: 1089–1099.PubMedCrossRefGoogle Scholar
  23. Tobin A.K., Sumar N., Patel M., Moore A.L. and Stewart G.R. (1988) Development of photorespiration during chloroplast biogenesis in wheat leaves. J. Exp. Bot. 39: 833–843.CrossRefGoogle Scholar
  24. Towbin H., Stahekin T. and Gordon J., (1979) Electrophoretic transfer of protein from polyacrylamide gels to nitrocellulose sheets. Proc. Natl. Acad. Sci. USA 76: 4350–4354.PubMedCrossRefGoogle Scholar
  25. Vally K.J.M., Selvi M.T. and Sharma R., (1995) Light alters cytosolic and plastidic phosphorylase distribution in pearl millet (Pennisetum americanum) leaves. Plant Physiol. 109: 517–523.PubMedGoogle Scholar
  26. Vernon L.P. (1960) Spectrophotometric determination of chlorophylls and phaeophytins in plant extracts. Anal. Chem. 32: 1144–1150.CrossRefGoogle Scholar
  27. Viro M. and Kloppstech K., (1980) Differential expression of the genes for ribulose 1, 5-bisphosphate carboxylase and light harvesting complex chlorophyll a/b protein in the developing barley leaf. Planta 150: 41–45.CrossRefGoogle Scholar
  28. Wernicke W. and Milkovits L. (1987) Effect of auxins on the mitotic cell cycle in cultured leaf segments at different stages of development in wheat. Physiol. Plant. 69: 16–22.CrossRefGoogle Scholar
  29. Wernicke W. and Milkovits L. (1987) Roles of uptake and metabolism of indole-3-acetic acid and 2–4 dichlorophenoxy acetic acid in cultured leaf segments at different stages of development in wheat. Physiol. Plant. 69: 23–28.CrossRefGoogle Scholar

Copyright information

© Prof. H.S. Srivastava Foundation for Science and Society 2008

Authors and Affiliations

  1. 1.School of Life SciencesUniversity of HyderabadHyderabadIndia

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