|Kazuyuki Saitou||Last modified date：2019.06.14|
Associate Professor / Agricultural Bioresource Sciences
Department of Bioresource Sciences
Faculty of Agriculture
Department of Bioresource Sciences
Faculty of Agriculture
Field of Specialization
Plant Production Physiology
Activities of enzymes related to starch synthesis were compared between two sweet potato cultivars, Koganesengan (a recently released high yield cultivar) and Tsurunasigenji (an old, local cultivar with poor yield). Activities of sucrose synthase (SuSy) and ADP-glucose pyrophosphorylase (AGPase) were higher in tuberous roots of Koganesengan than that of Tsurunasigenji. The activity of SuSy and AGPase in roots increased markedly following an increase in sucrose during development of the tuberous roots. Exogenous injection of sucrose solution into a plant effectively increase tuberous root production and the activity of SuSy and AGPase. The enzymatic activities were highly correlated with levels of mRNA.These results suggest that the activity of SuSy and AGPase is controlled by sucrose transported from leaves in mRNA level. To increase sweet potato production effectively, activities of SuSy and AGPase must be enhanced, and so a genetic and physiological improvement in photosynthetic funcion or sucrose productivity in leaves is necessary to increase activities of SuSy and AGPase in sink organs.
Research InterestsMembership in Academic Society
- Studies on histone deacetylases regulate the expression of photosynthesis genes in response to nitrogen supply in higher plants.
keyword : Nitrogen, Photosynthesis gene, Histone deacetylase, Transcriptional regulation, Higher plant
2014.04Regulation of expression of genes for Rubisco by nitrogen in rice.
- Studies on transcription factors which regulate the expression of photosynthesis genes in response to nitrogen supply in rice.
keyword : Nitrogen, Photosynthesis gene, Rice, Transcription factor, Transcriptional regulation
2005.04Regulation of expression of genes for Rubisco by nitrogen in rice.
- Transcription factors which regulate the expression of starch synthesis related genes and regulatory mechanisms in sweet potato.
keyword : Regulation of transcription, Starch synthesis, Sweet potato, Transcription factor
2006.04～2013.03Regulation of tuberous root formation by cycline D in sweet potato.
|1.||Kazuyuki Saitou, Nobuo Miyazaki, Ueno Osamu, Effects of nitrogen on the expression of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit multigene family members in rice (Oryza sativa L.), Plant Production Science, http://dx.doi.org/10.1626/pps.16.37, 16, 1, 37-40, 2013.01, [URL], Five ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit genes identified in the rice (Oryza sativa) genome are designated as OsRBCS1, 2, 3, 4 and 5. OsRBCS1 transcripts were not detectable. The mRNA levels of OsRBCS2, OsRBCS3, OsRBCS4 and OsRBCS5 in leaf blades were increased by NH4NO3 supply to nitrogen-starved plants, but the extent of increment varied with the genes. The mRNA levels of OsRBCS2, OsRBCS3 and OsRBCS4 in leaf blades were increased by NH4NO3 or glutamine supply to detached shoots. On the other hand, NH4NO3 and glutamine had little effect on the expression of OsRBCS5 gene. The mRNA level of OsRBCS4 was increased only by cytokinin supply to the detached shoots. The expression of the promoters of OsRBCS2 and OsRBCS3 was enhanced by NH4NO3 supply..|
|2.||Nagata, T., H. Hara, K. Saitou, A. Kobashi, K. Kojima, T. Yuasa and O. Ueno, Activation of ADP-glucose pyrophosphorylase gene promoters by a WRKY transcription factor, AtWRKY20, in Arabidopsis thaliana L. and sweet potato (Ipomoea batatas Lam.)., Plant production science, http://dx.doi.org/10.1626/pps.15.10, 15, 1, 10-18, 2012.01, [URL], AtWRKY20 functions directly as a transcriptional activator of the ApL3 promoter and regulates the expression of ApL3 induced by sucrose or osmoticum in A. thaliana. Moreover, AtWRKY20 can enhance the expression of the Koganesengan ibAGP1 promoter directly in sweet potato..|
|3.||Nagata, T. and K. Saitou, Regulation of expression of D3-type cyclins and ADP-glucose pyrophosphorylase genes by sugar, cytokinin and ABA in sweet potato (Ipomoea batatas Lam.)., Plant production science, 12, 4, 434-442, 2009.10, [URL].|
|4.||Oo, T.T., T., Araki, K. Saitou and F. Kubota, Response of growth, gas exchange and PSII electron transport in Greengram (Vigna radiata L., Wilczek) varieties and other pulse species to drought and re-watering, Journal of the faculty of agriculture Kyushu University, Vol. 53, No.1, 19-25, 2008.02.|
|5.||Satoh, A., K. Saitou and H. Okubo, Increase in the expression of an alpha-amylase gene and sugar accumulation induced during cold period reflects shoot elongation in hyacinth bulbs, Journal of the American society for horticulture science, 131、185-191, 2006.04.|
|1.||Regulation of the Expression of Rubisco Small Subunit Genes by a Nitrogen-Responsive Transcription Factor AtERF058 in Arabidopsis..|
|2.||Regulation of the Rubisco small subunit gene, RBCS1A, is regulated by interzction with histone deacetylase HDA5 in Arabidopsis..|
|3.||Regulation of the expression of RBCS1A by histone deacetylase HDA5 in Arabidopsis., [URL].|
|4.||Histone deacetylase HDA5 regulates the expression of RBCS1A in Arabidopsis., [URL].|
|5.||The expression divergence of two Rubisco small subunit genes, OsRBCS3 and OsRBCS5, in response to nitrogen supply correlates with dynamic changes in histone H3 modifications in rice., [URL].|
|6.||Alterations of lysine modifications on the histone H3 of a Rubisco small subunit gene, OsRBCS3, in response to nitrogen supply in rice., [URL].|
|7.||Role of a transcription factor with a single MYB domain, AtMYBN1, in response to nitrogen supply in Arabidopsis. , [URL].|
|8.||Transcriptional regulation of a Rubisco small subunit gene, OsRBCS3, by OsbZIP62 transcription factor in response to nitrogen limitation in rice. , [URL].|
|9.||Transcriptional regulation of a Rubisco small subunit gene, OsRBCS3, by OsDREB1E transcription factor in response to nitrogen supply in rice. , [URL].|
|10.||OsbZIP62 interacts with OsDREB1G transcription factor and represses transcription of a Rubisco small subunit gene, OsRBCS3, in response to nitrogen limitation in rice. , [URL].|
|11.||The rice OsDREB1G transcription factor regulates gene expression of Rubisco small subunit in response to nitrogen supply. , [URL].|
|12.||The rice OsHAP5C gene encoding a subunit of the CCAAT box binding complex regulates the expression of Rubisco small subunit gene in response to nitrogen supply. , [URL].|
|13.||The rice OsHAP5C gene encoding a subunit of the CCAAT box binding complex regulates transcription of a Rubisco small subunit gene, OsrbcS3, in response to nitrogen supply..|
|14.||Arabidopsis WRKY transcription factor AtWRKY20 activates transcription of an ADP-glucose pyrophosphorylase small subunit gene, ibAGP1, in sweet potato (Ipomoea batatas Lam.)..|
|15.||The AtWRKY20 transcription factor activates transcription of an ADP-glucose pyrophosphorylase large subunit gene, ApL3, in Arabidopsis thaliana..|
|16.||The AtWRKY20 transcription factor mediates the sugar- and abscisic acid- dependent expression of an ADP-glucose pyrophosphorylase large subunit gene (ApL3) in Arabidopsis thaliana., [URL].|
|17.||OsDof-6 regulates the expression of photosynthesis-related genes in response to nitrogen supply., [URL].|
|19.||Roles of Dof transcription factors in nitrogen-regulated gene expression of Rubisco small subunits in rice, [URL].|
- The Molecular Biology Society of Japan
- The Japanese Society of Plant Physiology
- Crop Science Society of Japan
- Japan Society for Bioscience, Biotechnology, and Agrochemistry
I am in charge of Topics in Applied Plant Physiology, Proseminar in Practical Botany I, Proseminar in Practical Botany II, Practicals for Soil Science and Plant Production I, Practicals for Soil Science and Plant Production II, Topics in Plant Resources, Tutorials on Applied Plant Production Physiology, Tutorial Exercise on Soil Science and Plant Production, Plant Biology, Laboratory Works in Agronomy I, Laboratory Works in Agronomy II, Laboratory Works in Agronomy III Laboratory and Works in Molecular Biology.
Professional and Outreach Activities
I lectured in country-focused training course in advanced research technology for sustainable agriculture development for Vietnam. Sweet potato (Ipomoea batatas Lam.) is the seventh most important food crop in the world, and has great potential in terms of the contribution it could make to the improvement of food security in developing countries. Two cultivars of sweet potato was used in this experiment; Koganesengan, a recently improved cultivar with high photosynthetic rate per unit leaf area and high yield; and Tsurunashigenji, a local traditional cultivar with low photosynthetic rate per unit leaf area and poor yield. Leaf structure was compared between Koganesengan and Tsurunashigenji..