Seed Fatty Acid Reducer acts downstream of gibberellin signalling pathway to lower seed fatty acid storage in Arabidopsis.
Previous studies based on microarray analysis have found that DELLAs down-regulate several GDSL genes in unopened flowers and/or imbibed seeds. This suggests the role of DELLAs in seed fatty acid (FA) metabolism. In the present study, enhancement of gibberellin (GA) signalling through DELLA mutation or exogenous gibberellin acid A3 (GA(3) ) resulted in the up-regulated expression of transcription factors for embryogenesis and seed development, genes involved in the FA biosynthesis pathway, and five GDSL-type Seed Fatty Acid Reducer (SFAR) genes. SFAR overexpression reduced the total seed FA content and led to a particular pattern of seed FA composition. This 'SFAR footprint' can also be found in plants with enhanced GA(3)  signalling. By contrast, the loss of SFAR function dramatically increases the seed FA content. The transgenic lines that overexpress SFAR were less sensitive to stressful environments, reflected by a higher germination rate and better seedling establishment compared with the wild type (WT) plants. The GDSL-type hydrolyzer is a family of proteins largely uncharacterized in Arabidopsis. Their biological function remains poorly understood. SFAR reduces seed FA storage and acts downstream of the GA signalling pathway. We provide the first evidence that some GDSL proteins are somehow involved in FA degradation in Arabidopsis seeds.
Key Laboratory of Crop Germplasm Resource of Zhejiang Province, College of Agriculture and Biotechnology, Hangzhou 310012, China.
Mingxun
M
Chen
Xue
X
Du
Yang
Y
Zhu
Zhong
Z
Wang
Shuijian
S
Hua
Zhilan
Z
Li
Wangli
W
Guo
Guoping
G
Zhang
Jinrong
J
Peng
Lixi
L
Jiang
D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005875:Gibberellins / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D016133:Polymerase Chain Reaction; D012639:Seeds / Q000201:enzymology*; D015398:Signal Transduction
D005227:Fatty Acids; D005875:Gibberellins; D010940:Plant Proteins; D000445:Aldehyde Oxidoreductases; C027902:fatty acid reductase