DynaMo Mini Symposium on plant transport processes

DynaMo Center is pleased to host a Mini Symposium on plant transport processes on Tuesday 21 April 2015.

Our two distinguished international guest a are:

Professor Kazufumi Yazaki, Kyoto University, Japan
Professor Enrico Martinoia, University of Zürich, Switzerland

Kazufumi Yazaki:

Membrane transporters involved in legume-microbe interactions
Legume plants sustain their growth even under low nitrogen condition as they have an ability to fix atmospheric nitrogen in nodules via symbiotic nitrogen fixation. In nodules, exchange of nutrients between host plant cells and their resident bacteria are required where membrane transporters should play pivotal roles. Various plant growth regulators are also to be relevant for the developmental processes of nodules, in which transporters regulating the movement of plant hormones should function in a highly regulated manner. To elucidate the metabolite dynamics relevant for symbiotic nitrogen fixation in nodules, we performed laser micro-dissection to isolate three cell-types from nodule tissues of a model legume Lotus japonicus. Transcriptome analysis revealed several ATP-binding cassette transporters and MATE-type transporters as well as metal transporters were highly expressed in infection zone. In the mini-symposium I will pick up a couple of transporters, e.g. LjABCB1 and LjMATE1, and introduce their characteristic expression pattern and discuss their possible physiological roles in nodules.

Enrico Martinoia:

The role of ABC transporters in abscisic acid and strigolactone transport
ABC transporters act as transporters for a large number of plant hormones. In this talk I will first summarize our actual knowledge on ABCG transporters involved in abscisic acid transport and and present new unpublished data we recently obtained. In the second part I will focus on the Petunia strigolcatone transporter PaPDR1, which has been shown to play an important role in mycorrhization and shoot branching. During the last years we were interested to elucidate how strigolactones are transported from their site of synthesis to the sites of action. To answer this question we produced plants expressing a PaPDR1-GFP construct and determined its localization. PaPDR1 exhibits a cell-type specific asymmetric localization in different root tissues. In root tips, PaPDR1 is co-expressed with the strigolactone biosynthetic gene DAD1 (CCD8) and it is localized at the apical membrane of root hypodermal cells, presumably mediating the shootward transport of strigolactone. Above the root tip, in the hypodermal passage cells that form gates for the entry of mycorrhizal fungi, PaPDR1 is present in the outer-lateral membrane, compatible with its postulated function as strigolactone exporter from roots to soil. I will discuss these results in relation with mycorrhization and plant architecture.

Everybody is velcome!