Diacylglycerol kinase ( Two independent Overexpression of Together, these results indicate that
Plant oils are valuable commodities for food, feed, renewable industrial feedstocks and biofuels. To increase vegetable oil production, here we show that the nonspecific phospholipase C6 (NPC6) promotes seed oil production in the Brassicaceae seed oil species Arabidopsis, Camelina and oilseed rape. Overexpression of Candidate‐gene association study in oilseed rape indicates that only These results indicate that NPC6 promotes membrane glycerolipid turnover to accumulate TAG production in oil seeds and that
- NSF-PAR ID:
- 10458790
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 226
- Issue:
- 4
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1055-1073
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary DGK ) phosphorylates diacylglycerol (DAG ) to generate phosphatidic acid (PA ), and bothDAG andPA are lipid mediators in the cell. Here we show thatDGK 1 in rice (Oryza sativa ) plays important roles in root growth and development.Os knockout (DGK 1‐dgk1 ) lines exhibited a higher density of lateral roots (LRs ) and thinner seminal roots (SRs ), whereasOs ‐overexpressing plants displayed a lowerDGK 1LR density and thickerSRs than wild‐type (WT ) plants.Os led to a decline in theDGK 1DGK substrateDAG whereas specificPA species decreased indgk1 roots. Supplementation ofDAG toOs ‐overexpressing seedlings restored theDGK 1LR density andSR thickness whereas application ofPA todgk1 seedlings restored theLR density andSR thickness to those of theWT . In addition, treatment of rice seedlings with theDGK inhibitor R59022 increased the level ofDAG and decreasedPA , which also restored the root phenotype ofOs ‐overexpressing seedlings close to that of theDGK 1WT .DGK 1 and associated lipid mediators modulate rice root architecture;DAG promotesLR formation and suppressesSR growth whereasPA suppressesLR number and promotesSR thickness. -
SUMMARY Heteromeric acetyl‐CoA carboxylase (htACCase) catalyzes the committed step of
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Summary l ‐Tyrosine is an essential aromatic amino acid required for the synthesis of proteins and a diverse array of plant natural products; however, little is known on how the levels of tyrosine are controlledin planta and linked to overall growth and development. Most plants synthesize tyrosine by TyrA arogenate dehydrogenases, which are strongly feedback‐inhibited by tyrosine and encoded byTyrA1 andTyrA2 genes inArabidopsis thaliana . While TyrA enzymes have been extensively characterized at biochemical levels, theirin planta functions remain uncertain. Here we found thatTyrA1 suppression reduces seed yield due to impaired anther dehiscence, whereasTyrA2 knockout leads to slow growth with reticulate leaves. Thetyra2 mutant phenotypes were exacerbated byTyrA1 suppression and rescued by the expression ofTyrA2 ,TyrA1 or tyrosine feeding. Low‐light conditions synchronized thetyra2 and wild‐type growth, and ameliorated thetyra2 leaf reticulation. After shifting to normal light,tyra2 transiently decreased tyrosine and subsequently increased aspartate before the appearance of the leaf phenotypes. Overexpression of the deregulated TyrA enzymes led to hyper‐accumulation of tyrosine, which was also accompanied by elevated aspartate and reticulate leaves. These results revealed that TyrA1 and TyrA2 have distinct and overlapping functions in flower and leaf development, respectively, and that imbalance of tyrosine, caused by altered TyrA activity and regulation, impacts growth and development of Arabidopsis. The findings provide critical bases for improving the production of tyrosine and its derived natural products, and further elucidating the coordinated metabolic and physiological processes to maintain tyrosine levels in plants. -
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Lipin1 deficiency leads to elevated expression levels of necroptotic markers, whereas restoration of lipin1 inhibits their expression.
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