Fatty acid α-dioxygenase from Pisum sativum: Temporal and spatial regulation during germination and plant development

• Published in: Journal of plant physiology 2009-03, Vol.166 (4), p.333-343
• Main Authors: Meisner, Anke K., Saffert, Alexander, Schreier, Peter, Schön, Astrid
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; Biological and medical sciences; complementary DNA; DNA libraries; DNA, Complementary - isolation & purification; enzyme activity; fatty acid alpha-dioxygenase; Fatty acid metabolism; Fundamental and applied biological sciences. Psychology; gene expression regulation; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Germination; Germination - genetics; Germination - physiology; Immunoblotting; long chain fatty acids; messenger RNA; molecular cloning; Molecular Sequence Data; Molecular Weight; oxidation; peas; peroxidases; Peroxidases - chemistry; Peroxidases - genetics; Peroxidases - metabolism; Phyto-oxylipins; Pisum sativum; Pisum sativum - enzymology; Pisum sativum - genetics; Pisum sativum - growth & development; Plant defense mechanism; plant development; Plant physiology and development; protein content; RNA, Messenger - genetics; RNA, Messenger - metabolism; seed development; seed germination; Sequence Alignment; sequence analysis; Sequence Analysis, Protein; Time Factors; tissue distribution; α-Oxidation
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2008.05.009

α-Dioxygenases are expressed in plants in response to biotic and abiotic stress. They catalyze the enantioselective 2-hydroperoxidation of long-chain fatty acids, the initial step of the α-oxidation pathway of fatty acids in plants. In this study, the complete cDNA of an α-dioxygenase from germinating pea seeds ( Pisum sativum) is presented. The deduced amino acid sequence establishes that the enzyme belongs to the recently characterized family of α-dioxygenating enzymes in plants. We also present the first systematic study on the expression of α-dioxygenase in germinating and developing pea plants. During germination, α-dioxygenase mRNA accumulates in the cotyledons and the embryonic axis of pea seeds de novo. In developing pea plants, the transcript is detected almost exclusively in roots. The accumulation of α-dioxygenase protein parallels transcript accumulation in that it is abundant in germinating as well as young plant tissue, and correlates with loss of mRNA during plant maturation. α-Dioxygenase enzymatic activity in plant extracts is highest in cotyledons during imbibition. In the embryonic axis and roots of developing plants comparable activity levels are observed, whereas in shoots little α-oxidation activity is detected. With this contribution, we present information on the temporal and spatial expression of α-dioxygenase during plant germination and development, supporting the hypothesis that the α-oxidation pathway of fatty acids plays a role during plant developmental processes.