Metal Tolerance Protein 8 Mediates Manganese Homeostasis and Iron Reallocation during Seed Development and Germination

Download
2017-07-01
Eroğlu, Seçkin
Meier, Bastian
Takahashi, Michiko
Terada, Yasuko
Ignatyev, Konstantin
Andresen, Elisa
Kupper, Hendrik
Peiter, Edgar
Von Wiren, Nicolaus
Metal accumulation in seeds is a prerequisite for germination and establishment of plants but also for micronutrient delivery to humans. To investigate metal transport processes and their interactions in seeds, we focused on METAL TOLERANCE PROTEIN8 (MTP8), a tonoplast transporter of the manganese (Mn) subclade of cation diffusion facilitators, which in Arabidopsis (Arabidopsis thaliana) is expressed in embryos of seeds. The x-ray fluorescence imaging showed that expression of MTP8 was responsible for Mn localization in subepidermal cells on the abaxial side of the cotyledons and in cortical cells of the hypocotyl. Accordingly, under low Mn availability, MTP8 increased seed stores of Mn, required for efficient seed germination. In mutant embryos lacking expression of VACUOLAR IRON TRANSPORTER1 (VIT1), MTP8 built up iron (Fe) hotspots in MTP8-expressing cells types, suggesting that MTP8 transports Fe in addition to Mn. In mtp8 vit1 double mutant seeds, Mn and Fe were distributed in all cell types of the embryo. An Fe transport function of MTP8 was confirmed by its ability to complement Fe hypersensitivity of a yeast mutant defective in vacuolar Fe transport. Imbibing mtp8-1 mutant seeds in the presence of Mn or subjecting seeds to wet-dry cycles showed that MTP8 conferred Mn tolerance. During germination, MTP8 promoted reallocation of Fe from the vasculature. These results indicate that cell type-specific accumulation of Mn and Fe in seeds depends on MTP8 and that this transporter plays an important role in the generation of seed metal stores as well as for metal homeostasis and germination efficiency under challenging environmental conditions.
PLANT PHYSIOLOGY

Suggestions

Inheritance of wood specific gravity and its genetic correlation with growth traits in young pinus brutia progenies
Yıldırım, Kubilay; Kaya, Zeki; Department of Biotechnology (2008)
In long term, to discover the genes responsible for wood production, genetic control of wood specific gravity (WSG) in Pinus brutia Ten. (Turkish red pine) open pollinated Ceyhan progeny trial, which was established with the seeds collected from 168 clones originated from six clonal Turkish red pine seed orchards was studied. Wood samples were taken by destructive sampling during the rouging of this trial at the age of seven. Specifically; (1) to examine the magnitude of family differences and its component...
Plasmalemma from the roots of cucumber: Isolation by two-phase partitioning and characterization
Memon, Abdul Razaque; Sommarin, Marianne; Kylin, Anders (Wiley, 1987-2)
Plasmalemma was isolated from the roots of 2‐week‐old cucumber plants (Cucumis sativus L. cv. Rhensk druv) by utilizing an aqueous polymer two‐phase system with 6.5%:6.5% (w/w) Dextran T500 and polyethylene glycol (PEG) 3350 at pH 7.8. The plasmalemma fraction comprised ca 6% of the membrane proteins contained in the microsomal fraction. The specific activity of the plasma membrane marker enzyme (K+, Mg2+‐ATPase) was 14‐ to 17‐times higher in the upper (PEG‐rich) than in the lower (Dextran‐rich) phase, and ...
Evaluation of photosynthetic performance of wheat cultivars exposed to boron toxicity by the JIP fluorescence test
Oz, M. T.; TURAN, ÖZLEM; Kayihan, C.; EYİDOĞAN, FÜSUN; EKMEKÇİ, YASEMİN; YÜCEL, MUSTAFA; Öktem, Hüseyin Avni (Institute of Experimental Botany, 2014-12-01)
The changes in growth and photosynthetic performance of two wheat (Triticum aestivum L.) cultivars (Bolal-2973 and Atay-85) differing in their sensitivity to boron (B) toxicity were investigated under toxic B conditions. Eight-day old seedlings were exposed to highly toxic B concentrations (5, 7.5, and 10 mM H3BO3) for 5 and 9 days. Fast chlorophyll a fluorescence kinetics was determined and analysed using JIP test. Growth parameters, tissue B contents, and membrane damage were measured at two stress durati...
Genetic transformation of lentil ( Lens culinaris m. cv.Sultan.1) with a transcription factor regulator (MBF1c) and analysis of transgenic plants
Kamçı, Hamdi; Çelikkol Akçay, Ufuk; Kamçı, Hamdi; Department of Biotechnology (2011)
Agrobacterium mediated genetic transformation of lentil Sultan 1 cultivar with MBF1c and evaluation of transgenic plants was aimed. The study was initially based on optimized protocol with Agrobacterium tumefaciens KYRT1 strain and pTJK136 binary plasmid. Based on this protocol and transient marker gene expression in embryo apex, 15% stable transformation efficiency was aimed. However limited knowledge about pTJK136 and problem with curing KYRT1 leaded us to use Agrobacterium tumefaciens C58C1 strain and al...
Genetic diversity of scald (rhynchosporium secalis) disease resistant and sensitive Turkish barley seed sources as determined with simple sequence repeats
Dizkırıcı, Ayten; Kaya, Zeki; Department of Biology (2006)
Scald disease (Rhynchosporium secalis) is one of the major plant diseases causing considerable yield loss in barley (Hordeum vulgare) plantations in Turkey. To develop, scald resistant barley varieties, C.R.I.F.C. of Turkey has a large accumulated collection of barley seed sources in hand, but these samples are difficult to be followed and used in the breeding programs due to lack of genetic studies on them. Thus, the objective of this study was to characterize and fingerprint of eighty barley seed sources,...
Citation Formats
S. Eroğlu et al., “Metal Tolerance Protein 8 Mediates Manganese Homeostasis and Iron Reallocation during Seed Development and Germination,” PLANT PHYSIOLOGY, pp. 1633–1647, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/34805.