AJPS  Vol.9 No.6 , May 2018
Detection of Sugar-Regulated Gene Expression and Signaling in Suspension-Cultured Rice Cells
Author(s) Shin-Lon Ho

To better understand the mechanism of sugar signaling in rice cell, the suspension-cultured rice cells were transferred from sucrose-containing (+S) to sucrose-free (-S) of MS culture medium, we found that ribosomal RNAs (rRNAs) were degraded progressively. This suggests that carbon, nitrogen, and phosphate were recycled in this process and the reduction in cellular rRNAs might lead to decreased translation to save energy in response to sugar starvation. Differential screening revealed that two groups of genes, sugar-starvation-repressed (SSR) and sugar-starvation-activated (SSA) genes, were regulated by sugar in an opposing manner. Northern-blot analysis showed that two major hybridization signals of 0.8 and 1.9 kb were induced strongly under sugar starvation. The two populations of genes corresponded with homologs of α-amylases (1.9 kb) and the glycine-rich proteins (GRPs) gene family (0.8 kb), and all were SSA genes. Expression of GRP genes was strongly induced in sugar-starved cells, which suggests that GRPs may help to protect cells against nutritional stress. Treatment of +S and -S cells with the protein kinase (PK) inhibitor staurosporine (St) and the serine/theronine phosphoprotein phosphatases 1 (PP1) and 2A (PP2A) inhibitor okadaic acid (OA) revealed that PP1 and PP2A (PPs) might be involved in increasing SSR gene expression in +S cells, and that activation of the majority of the SSA genes in -S cells might be due to PKs activity. These results suggested that PKs and PPs might be involved in the sugar regulation of SSR and SSA gene expression. An in-gel PK activity assay demonstrated that the activity of two classes of PKs (50 and 66 kDa) may be induced rapidly after transfer of +S cells to -S medium. Following transfer of -S cells to +S medium, a novel class of 38 kDa PK was induced rapidly and showed high activity. The 38 kDa PK might play a role in sugar sensing, and the 50 and 66 kDa PKs might play roles in signal sensing under sugar starvation in rice cells. These results provide valuable information on three classes of protein kinases that might play key roles in sugar sensing and signaling in rice.

Cite this paper
Ho, S. (2018) Detection of Sugar-Regulated Gene Expression and Signaling in Suspension-Cultured Rice Cells. American Journal of Plant Sciences, 9, 1124-1142. doi: 10.4236/ajps.2018.96085.
[1]   Granot, D., David-Schwartz, R. and Kelly, G. (2013) Hexose Kinases and Their Role in Sugar-Sensing and Plant Development. Frontiers in Plant Science, 4, 44.

[2]   Lastdrager, J., Hanson, J. and Smeekens, S. (2014) Sugar Signals and the Control of Plant Growth and Development. Journal of Experimental Botany, 65, 799-807.

[3]   Ho, S.L., Chao, Y.C., Tong, W.F. and Yu, S.M. (2001) Sugar Coordinately and Differentially Regulates Growth and Stress-Related Gene Expression via a Complex Signal Transduction Network and Multiple Control Mechanisms. Plant Physiology, 125, 877-890.

[4]   Koch, K.E. (1996) Carbohydrate-Modulated Gene Expression in Plants. Annual Review of Plant Physiology and Plant Molecular Biology, 47, 509-540.

[5]   Yu, S.M. (1999) Cellular and Genetic Responses of Plants to Sugar Starvation. Plant Physiology, 121, 687-693.

[6]   Jefferson, R., Goldsbrough, A. and Bevan, M. (1990) Transcriptional Regulation of a Patatin-1 Gene in Potato. Plant Molecular Biology, 14, 995-1006.

[7]   Hattori, T., Nakagawa, S. and Nakamura, K. (1990) High Level Expression of Tuberous Root Storage Protein Genes of Sweet Potato in Stems of Plantlets Grown in Vitro on Sucrose Medium. Plant Molecular Biology, 14, 595-604.

[8]   Müller-Rober, B.T., Kobmann, J., Hannah, L.C., Willmitzer, L. and Sonnewald, U. (1990) One of Two Different ADP-Glucose Pyrophosphorylase Genes from Potato Responds Strongly to Elevated Levels of Sucrose. Molecular Genetics and Genomics, 224, 136-146.

[9]   Yu, S.M., Kuo, Y.H., Sheu, G., Sheu, Y.J. and Liu, L.F. (1991) Metabolic Derepression of α-Amylase Gene Expression in Suspension-Cultured Cells of Rice. Journal of Biological Chemistry, 266, 21131-21137.

[10]   Yu, S.M., Lee, Y.C., Fang, S.C., Chan, M.T., Hwa, S.F. and Liu, L.F. (1996) Sugar Act as Signal Molecules and Osmotica to Regulate the Expression of α-Amylase Genes and Metabolic Activities in Germinating Cereal Grains. Plant Molecular Biology, 30, 1277-1289.

[11]   Krapp, A., Hofmann, B., Schafer, C. and Stitt, M. (1993) Regulation of the Expression of rbcS and Other Photosynthetic Genes by Carbohydrates: A Mechanism for the “Sink Regulation” of Photosynthesis? The Plant Journal, 3, 817-828.

[12]   Sheen, J. (1990) Metabolic Repression of Transcription in Higher Plants. The Plant Cell, 2, 1027-1038.

[13]   Contento, A.L., Ki, S.J. and Bassham, D.C. (2004) Transcriptome Profiling of the Response of Arabidopsis Suspension Culture Cells to Suc Starvation. Plant Physiology, 135, 2330-2347.

[14]   Sheu, J.J., Jan, S.P., Lee, H.T. and Yu, S.M. (1994) Control of Transcription and mRNA Turnover as Mechanisms of Metabolic Repression of α-Amylase Gene Expression. The Plant Journal, 5, 655-664.

[15]   Sheu, J.J., Yu, T.S., Tong, W.F. and Yu, S.M. (1996) Carbohydrate Starvation Stimulates Differential Expression of Rice α-Amylase Genes That Is Modulated through Complicated Transcriptional and Posttranscriptional Processes. Journal of Biological Chemistry, 271, 26998-27004.

[16]   Chan, M.T. and Yu, S.M. (1998) The 3’-Untranslated Region of a Rice α-Amylase Gene Functions as a Sugar-Dependent mRNA Stability Determinant. Proceedings of the National Academy of Sciences of the United States of America, 95, 6543-6547.

[17]   Hwang, Y.S., Karrer, E.E., Tomas, B.R., Chen, L. and Rodriguez, R.L. (1998) Three Cis-Elements Required for Rice α-Amylase Amy3D Expression during Sugar Starvation. Plant Molecular Biology, 36, 331-341.

[18]   Lu, C.A., Lim, E.K. and Yu, S.M. (1998) Sugar Response Sequence in the Promoter of a Rice α-Amylase Gene Serves as a Transcriptional Enhancer. Journal of Biological Chemistry, 273, 10120-10131.

[19]   Lu, C.A., Ho, T.H.D., Ho, S.L. and Yu, S.M. (2002) Three Novel MYB Proteins with One DNA Binding Repeat Mediate Sugar and Hormone Regulation of α-Amylase Gene Expression. The Plant Cell, 14, 1963-1980.

[20]   Jang, J.C. and Sheen, J. (1997) Sugar Sensing in Higher Plants. Trends in Plant Science, 2, 208-213.

[21]   Sheen, J., Zhou, L. and Jang, J.C. (1999) Sugars as Signaling Molecules. Current Opinion in Plant Biology, 2, 410-418.

[22]   Rolland, F., Moore, B. and Sheen, J. (2002) Sugar Sensing and Signaling in Plants. The Plant Cell, 14, S185-S205.

[23]   Moore, B., Zhou, L., Rolland, F., Hall, Q., Cheng, W.H., Liu, Y.X., et al. (2003) Role of the Arabidopsis Glucose Sensor HXK1 in Nutrient, Light, and Hormonal Signaling. Science, 300, 332-336.

[24]   Rolland, F., Baena-Gonzalez, E. and Sheen, J. (2006) Sugar Sensing and Signaling in Plants: Conserved and Novel Mechanisms. Annual Review of Plant Biology, 57, 675-709.

[25]   Smeekens, S. and Rook, F. (1997) Sugar Sensing and Sugar-Mediated Signal Transduction in Plants. Plant Physiology, 115, 7-13.

[26]   Halford, N.G., Purcell, P.C. and Grahame, H.D. (1999) Is Hexokinase Really a Sugar Sensor in Plants? Trends in Plant Science, 4, 117-120.

[27]   Smeekens, S. (2000) Sugar-Induced Signal Transduction in Plants. Annual Review of Plant Physiology and Plant Molecular Biology, 51, 49-81.

[28]   Hanson, J. and Smeekens, S. (2009) Sugar Perception and Signaling—An Update. Current Opinion in Plant Biology, 12, 562-567.

[29]   Smeekens, S. and Hellmann, H.A. (2014) Sugar Sensing and Signaling in Plants. Frontier in Plant Sciences, 5, 113.

[30]   Purcell, P.C., Smith, A.M. and Halhord, N.G. (1998) Antisense Expression of a Sucrose Non-Fermenting-1-Related Protein Kinase Sequence in Potato Results in Decreased Expression of Sucrose Synthase in Tubers and Loss of Sucrose-Inducibility of Sucrose Synthase Transcripts in Leaves. The Plant Journal, 14, 195-202.

[31]   Laurie, S., Mckibbin, R.S. and Halford, N.G. (2003) Antisense SNF1-Related (SnRK1) Protein Kinase Gene Represses Transient Activity of an α-Amylase (α-Amy2) Gene Promoter in Cultured Wheat Embryos. Journal of Experimental Botany, 54, 739-747.

[32]   Lu, C.A., Lin, C.C., Lee, K.W., Chen, J.L., Huang, L.F., Ho, S.L., Liu, H.J., Hsing, Y.I. and Yu, S.M. (2007) The SnRK1A Protein Kinase Plays a Key Role in Sugar Signaling during Germination and Seedling Growth of Rice. The Plant Cell, 19, 2484-2499.

[33]   Paul, M.J., Primavesi, L.F., Jhurreea, D. and Zhang, Y. (2008) Trehalose Metabolism and Signaling. Annual Review of Plant Biology, 59, 417-441.

[34]   Avonce, N., Leyman, B., Mascorro-Gallardo, J.O., Van Dijck, P., Thevelein, J.M. and Iturriaga, G. (2004) The Arabidopsis Trehalose-6-P Synthase AtTPS1 Gene Is a Regulator of Glucose, Abscisic Acid, and Stress Signaling. Plant Physiology, 136, 3649-3659.

[35]   Zhang, Y., Primavesi, L.F., Jhurreea, D., Andralojc, P.J., Mitchell, R.A., Powers, S.J., Schluepmann, H., Delatte, T., Wingler, A. and Paul, M.J. (2009) Inhibition of SNF1-Related Protein Kinase1 Activity and Regulation of Metabolic Pathways by Trehalose-6-Phosphate. Plant Physiology, 149, 1860-1871.

[36]   Murashige, T. and Skoog, F. (1962) A Revised Medium for Rapid Growth and Bioassays with Tobacco Tissue Cultures. Physiologia Plantarum, 15, 473-497.

[37]   Braford, M.M. (1976) A Rapid and Sensitive Method for the Quantification of Microgram Quantities of Protein Utilizing the Principle of Protein Dye Binding. Analytical Biochemistry, 112, 195-203.

[38]   Mizoguchi, T., Gotoh, Y., Nishida, E., Yamaguchi-Shinozaki, K., Hayashida, N., Iwasaki, T., Kamada, H. and Shinozaki, K. (1994) Characterization of Two cDNAs that Encode MAP Kinase Homologues in Arabidopsis thaliana and Analysis of the Possible Role of Auxin in Activating Such Kinase Activities in Cultured Cells. The Plant Journal, 5, 111-122.

[39]   Usami, S., Banno, H., Ito, Y., Nishihama, R. and Machida, Y. (1995) Cutting Activates a 46-Kilodalton Protein Kinase in Plants. Proceedings of the National Academy of Sciences of the United States of America, 92, 8660-8664.

[40]   Uchimiya, H., Kidou, S.I., Shimazaki, T., Aotsuka, S., Takamatsu, S., Nishi, R., Hashimoto, H., Matsubayashi, Y., Kidou, N., Umeda, M. and Kato, A. (1992) Random Sequencing of cDNA Libraries Reveals a Variety of Expressed Genes in Cultured Cells of Rice (Oryza sativa L.). The Plant Journal, 2, 1005-1009.

[41]   Condit, C.M. and Meagher, R.B. (1987) Expression of a Gene Encoding a Glycine-Rich Protein in Petunia. Molecular Cell Biology, 7, 4273-4279.

[42]   Gómez, J., Sanchez-Martinez, D., Stiefel, R., Rigau, J., Puigdomènech, P. and Pagès, M. (1998) A Gene Induced by the Plant Hormone Abscisic Acid in Response to Water Stress Encodes a Glycine-Rich Protein. Nature, 334, 262-264.

[43]   De Oliveira, D.E., Seurinck, J., Inzé, D., van Montagu, M. and Botterman, J. (1990) Differential Expression of Five Arabidopsis Genes Encoding Glycine-Rich Proteins. The Plant Cell, 2, 427-436.

[44]   Fang, R.X., Pang, Z., Gao, D.M., Mang, K.Q. and Chua, N.H. (1991) cDNA Sequence of a Virus-Inducible, Glycine-Rich Protein Gene from Rice. Plant Molecular Biology, 17, 1255-1257.

[45]   Cheng, S.H., Keller, B. and Condit, C.M. (1996) Common Occurrence of Homologues of Petunia Glycine-Rich Protein-1 among Plants. Plant Molecular Biology, 31, 163-168.

[46]   Showalter, A.M. (1993) Structure and Function of Plant Cell Wall Proteins. The Plant Cell, 5, 9-23.

[47]   Ringli, C., Keller, B. and Ryser, U. (2001) Glycine-Rich Proteins as Structural Components of Plant Cell Walls. Cellular and Molecular Life Sciences, 58, 1430-1441.

[48]   Pego, J.V., Weisbeek, P.T. and Smeekens, S.C.M. (1999) Mannose Inhibits Arabidopsis Germination via a Hexokinase-Mediated Step. Plant Physiology, 119, 1017-1024.

[49]   Sheen, J. (1993) Protein Phosphatase Activity Is Required for Light-Inducible Gene Expression in Maize. The EMBO Journal, 12, 3497-3505.

[50]   Ehness, R., Ecker, M., Godt, D.E. and Roitsch, T. (1997) Glucose and Stress Independently Regulate Source and Sink Metabolism and Defense Mechanisms via Signal Transduction Pathways Involving Protein Phosphorylation. The Plant Cell, 9, 1825-1841.

[51]   Kholodenko, B.N. (2006) Cell Signalling Dynamics in Time and Space. Nature Review Molecular Cell Biology, 7, 165-176.