Omega-3 fatty acid desaturase genes isolated from purslane (Portulaca oleracea L.): expression in different tissues and response to cold and wound stress.

Abstract

Two full-length cDNA clones PoleFAD7 and PoleFAD8, encoding plastidial omega-3 fatty acid desaturases were isolated from purslane (Portulaca oleracea). The encoded enzymes convert linoleic to alpha-linolenic acid (C18:3n-3). Three histidine clusters characteristic of fatty acid desaturases, a putative chloroplast transit peptide in the N-terminal, and three putative transmembrane domains were identified in the sequence. Both genes were expressed in all analyzed tissues showing different levels of expression. PoleFAD7 was up-regulated by wounding but not by low temperature. PoleFAD8 was up-regulated by cold stress but not by wounding. Total fatty acid and linolenic acid content were higher both, in wounded and intact leaves of plants exposed to low temperature.

• Authors: Monica C Teixeira, Isabel S Carvalho, Maria Brodelius
• Journal: Journal of agricultural and food chemistry (J Agric Food Chem) Vol. 58 Issue 3 Pg. 1870-7 (Feb 10 2010) ISSN: 1520-5118 [Electronic] United States
• PMID: 20070085 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Plant Proteins
• Fatty Acid Desaturases
• omega-3 fatty acid desaturase

Topics

• Cold Temperature
• Fatty Acid Desaturases (chemistry, genetics, metabolism)
• Gene Expression Regulation, Enzymologic
• Gene Expression Regulation, Plant
• Molecular Sequence Data
• Plant Proteins (chemistry, genetics, metabolism)
• Portulaca (chemistry, enzymology, genetics, physiology)
• Protein Structure, Tertiary
• Stress, Physiological