Omega-3 fatty acid desaturase genes isolated from purslane (Portulaca oleracea L.): expression in different tissues and response to cold and wound stress.
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.
Teixeira
Monica C
MC
University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
Carvalho
Isabel S
IS
Brodelius
Maria
M
D003080:Cold Temperature; D044943:Fatty Acid Desaturases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D031822:Portulaca / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D017434:Protein Structure, Tertiary; D013312:Stress, Physiological
D010940:Plant Proteins; D044943:Fatty Acid Desaturases; C078565:omega-3 fatty acid desaturase