| RRC ID |
608
|
| Author |
Pruzinská A, Tanner G, Aubry S, Anders I, Moser S, Müller T, Ongania KH, Kräutler B, Youn JY, Liljegren SJ, Hörtensteiner S.
|
| Title |
Chlorophyll breakdown in senescent Arabidopsis leaves. Characterization of chlorophyll catabolites and of chlorophyll catabolic enzymes involved in the degreening reaction.
|
| Journal |
Plant Physiol
|
| Abstract |
During senescence, chlorophyll (chl) is metabolized to colorless nonfluorescent chl catabolites (NCCs). A central reaction of the breakdown pathway is the ring cleavage of pheophorbide (pheide) a to a primary fluorescent chl catabolite. Two enzymes catalyze this reaction, pheide a oxygenase (PAO) and red chl catabolite reductase. Five NCCs and three fluorescent chl catabolites (FCCs) accumulated during dark-induced chl breakdown in Arabidopsis (Arabidopsis thaliana). Three of these NCCs and one FCC (primary fluorescent chl catabolite-1) were identical to known catabolites from canola (Brassica napus). The presence in Arabidopsis of two modified FCCs supports the hypothesis that modifications, as present in NCCs, occur at the level of FCC. Chl degradation in Arabidopsis correlated with the accumulation of FCCs and NCCs, as well as with an increase in PAO activity. This increase was due to an up-regulation of Pao gene expression. In contrast, red chl catabolite reductase is not regulated during leaf development and senescence. A pao1 knockout mutant was identified and analyzed. The mutant showed an age- and light-dependent cell death phenotype on leaves and in flowers caused by the accumulation of photoreactive pheide a. In the dark, pao1 exhibited a stay-green phenotype. The key role of PAO in chl breakdown is discussed.
|
| Volume |
139(1)
|
| Pages |
52-63
|
| Published |
2005-9-1
|
| DOI |
10.1104/pp.105.065870
|
| PII |
pp.105.065870
|
| PMID |
16113212
|
| PMC |
PMC1203357
|
| MeSH |
Apoptosis Regulatory Proteins / metabolism
Arabidopsis / enzymology*
Arabidopsis / metabolism
Arabidopsis Proteins / metabolism
Cell Death
Chlorophyll / analogs & derivatives*
Chlorophyll / chemistry
Chlorophyll / metabolism*
DNA, Bacterial / genetics
Gene Expression Regulation, Enzymologic
Gene Expression Regulation, Plant
Light
Molecular Structure
Mutagenesis, Insertional / genetics
Oxidoreductases / metabolism
Oxygenases / genetics
Oxygenases / metabolism
Phenotype
Plant Leaves / enzymology
Plant Leaves / growth & development*
Plant Leaves / metabolism*
Time Factors
|
| IF |
6.902
|
| Times Cited |
196
|
|
WOS Category
|
PLANT SCIENCES
|
| Resource |
| Arabidopsis / Cultured plant cells, genes |
pda07874 |
