This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 20/2/452    most recent tpc.107.054718v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Plant Cell Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Google Scholar Articles by Maeda, H. Articles by DellaPenna, D. PubMed PubMed Citation Articles by Maeda, H. Articles by DellaPenna, D. Agricola Articles by Maeda, H. Articles by DellaPenna, D.

Tocopherols Modulate Extraplastidic Polyunsaturated Fatty Acid Metabolism in Arabidopsis at Low Temperature^[W]

^a Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
^b Cell and Molecular Biology Program, Michigan State University, East Lansing, Michigan 48824
^c Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada M5S 3B2
^d Kansas Lipidomics Research Center, Division of Biology, Kansas State University, Manhattan, Kansas 66506

² Address correspondence to dellapen{at}msu.edu.

Tocopherols (vitamin E) are synthesized in plastids and have long been assumed to have essential functions restricted to these organelles. We previously reported that the vitamin e-deficient2 (vte2) mutant of Arabidopsis thaliana is defective in transfer cell wall development and photoassimilate transport at low temperature (LT). Here, we demonstrate that LT-treated vte2 has a distinct composition of polyunsaturated fatty acids (PUFAs): lower levels of linolenic acid (18:3) and higher levels of linoleic acid (18:2) compared with the wild type. Enhanced 18:3 oxidation was not involved, as indicated by the limited differences in oxidized lipid species between LT-treated vte2 and the wild type and by a lack of impact on the LT-induced vte2 phenotype in a vte2 fad3 fad7 fad8 quadruple mutant deficient in 18:3. PUFA changes in LT-treated vte2 occur primarily in phospholipids due to reduced conversion of dienoic to trienoic fatty acids in the endoplasmic reticulum (ER) pathway. Introduction of the ER fatty acid desaturase mutation, fad2, and to a lesser extent the plastidic fad6 mutation into the vte2 background suppressed the LT-induced vte2 phenotypes, including abnormal transfer cell wall development. These results provide biochemical and genetic evidence that plastid-synthesized tocopherols modulate ER PUFA metabolism early in the LT adaptation response of Arabidopsis.

Related articles in Plant Cell:

Tocopherols and ER Fatty Acid Metabolism

Nancy A. Eckardt
Plant Cell 2008 20: 246. [Full Text]  

This article has been cited by other articles:

				N. A. Eckardt Tocopherols and ER Fatty Acid Metabolism PLANT CELL, February 1, 2008; 20(2): 246 - 246. [Full Text] [PDF]