This page is English information of our laboratory.

IPSR, Okayama Univ.

Group of Plant Molecular Physiology

Group Reader

Prof. Maki Katsuhara

Access

〒076-0046
Chuo 2-20-1, Kurashiki, Okayama, Japan
→Access
TEL. +81-86-434-1221
FAX. +81-86-434-1249

Contact

Please send e-mail to kmaki(AT)okayama-u.ac.jp (please change (AT) to @, when you send email)

Research Topic

We have been conducting cellular, membrane-biological, and molecular studies on the responses of plants to soil environmental stresses. Now our focus is on the function and regulation of aquaporins as transporters for water in salt/osmotic stress. Furthermore, we focused on aluminum (Al) ion, a major inhibitory factor of plant growth in acidic soils, and has been analyzing the mechanisms of Al toxicity and tolerance, using a cultured cell system and whole plants.

Research 1

Mechanism and regulation of transporters for water, low molecular compounds, and ions on the response to salt stress.

We reported that a few salt tolerant rice and barley cultivars had reduced the root water conductance as an early reaction after salt stress. Now we are conducting the study to reveal regulators for this response. We are also analyzing aquaporins transporting low molecular weight compounds (H2O2, CO2) in addition to water. Furthermore, we are conducting molecular and functional analysis of ion transporters under salt stress.

An aquaporin facillitaing the memebrane transport of water and CO2

Research 2

Aluminum toxicity and tolerant mechanisms in plants

We study mechanisms of aluminum (Al) induced cell deash and root growth inhibition using tobacco cultured cells and plants. Recently, we showed relation to vacuolar prossessing enzyme (VPE) and sucrose transporter. Furthermore, we are analyzing that wheat Al-tolerant gene, ALMT1, which encodes Al-activated malate transporter. Now, the structural and functional analyses (eg. activation mechanism by Al) are studied. In addition, since the ALMT-protein family is specific to plants, functional diversity of the ALMT1 homologues is studied.

Wheat aluminum tolerant gene, ALMT1 (Aluminum-activated malate transporter 1)

Research 3

Ion channels on the respose to environmental stresses

Salt stress induces the excess Na+ influx and/or inhibits the uptake of K+, an essential mineral for plants. Al+ induces the efflux of malate via ALMT1. We analyze such ion fluxs and related channels/transporters with the heterologous gene expression system in Xenopus oocytes, and electrophysiological measurements.

Electrophysiological measurement in the oocyte expressing a plant ion transporter

History of our laboratory

1, April 2017

Our group was started from this year. Now 8 members are studying in this laboratory.