title: Accumulation of starch in Zn-deficient rice.
abstract: Zinc (Zn) is an essential micronutrient for living organisms, and understanding the molecular mechanisms of Zn deficiency may help to develop strategies to mitigate this problem. Microarray analysis of Zn deficient rice revealed the up-regulation of several genes involved in Zn transport. Moreover many genes involved in starch synthesis/transport were up-regulated by Zn deficiency in rice roots and shoots. Furthermore, starch granules were detected mainly in the cortical cells of these tissues. The gene encoding inactive RNase was much more highly transcribed than those encoding active RNases. Although the level of RNA degradation in a crude extract of Zn-deficient shoots was higher than that of Zn-sufficient shoots, addition of Zn significantly reduced the level of degradation. These results indicate that RNA degradation could be regulated by the amount of Zn in the cell, and that the tolerance of rice plants to low levels of Zn is promoted by the accumulation of starch and inactive RNase.
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Motofumi
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Khurram
authors.initials: K
authors.lastname: Bashir
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Inoue
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Nakanishi
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan. annaoko@mail.ecc.u-tokyo.ac.jp.|Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi-shi, Ishikawa, 921-8836, Japan. annaoko@mail.ecc.u-tokyo.ac.jp.
authors.forename: Naoko K
authors.initials: NK
authors.lastname: Nishizawa
keywords: Microarray; RNase; Rice; Starch accumulation; Zinc; Zinc deficiency