TY  - JOUR
A1  - Kamranfar, Iman
A1  - Xue, Gang-Ping
A1  - Tohge, Takayuki
A1  - Sedaghatmehr, Mastoureh
A1  - Fernie, Alisdair R.
A1  - Balazadeh, Salma
A1  - Mueller-Roeber, Bernd
T1  - Transcription factor RD26 is a key regulator of metabolic reprogramming during dark-induced senescence
JF  - New phytologist : international journal of plant science
N2  - Leaf senescence is a key process in plants that culminates in the degradation of cellular constituents and massive reprogramming of metabolism for the recovery of nutrients from aged leaves for their reuse in newly developing sinks. We used molecular-biological and metabolomics approaches to identify NAC transcription factor (TF) RD26 as an important regulator of metabolic reprogramming in Arabidopsis thaliana. RD26 directly activates CHLOROPLAST VESICULATION (CV), encoding a protein crucial for chloroplast protein degradation, concomitant with an enhanced protein loss in RD26 over-expressors during senescence, but a reduced decline of protein in rd26 knockout mutants. RD26 also directly activates LKR/SDH involved in lysine catabolism, and PES1 important for phytol degradation. Metabolic profiling revealed reduced c-aminobutyric acid (GABA) in RD26 overexpressors, accompanied by the induction of respective catabolic genes. Degradation of lysine, phytol and GABA is instrumental for maintaining mitochondrial respiration in carbon-limiting conditions during senescence. RD26 also supports the degradation of starch and the accumulation of mono-and disaccharides during senescence by directly enhancing the expression of AMY1, SFP1 and SWEET15 involved in carbohydrate metabolism and transport. Collectively, during senescence RD26 acts by controlling the expression of genes across the entire spectrum of the cellular degradation hierarchy.
KW  - Arabidopsis
KW  - fatty acid
KW  - primary metabolism
KW  - protein and amino acid degradation
KW  - respiration
KW  - senescence
Y1  - 2018
U6  - https://doi.org/10.1111/nph.15127
SN  - 0028-646X
SN  - 1469-8137
VL  - 218
IS  - 4
SP  - 1543
EP  - 1557
PB  - Wiley
CY  - Hoboken
ER  -