The relationship between pyridine nucleotides and seed dormancy

To investigate the proposed role for NAD metabolism in regulating seed dormancy, NAD metabolites and associated enzyme activities were analysed in seed of Arabidopsis thaliana ecotypes ranging from Col-0, which has low seed dormancy, to Cvi, which is highly dormant. Seed poly(ADP-ribosyl)ation level...

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Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 181(2009), 1 vom: 15., Seite 62-70
1. Verfasser: Hunt, Lee (VerfasserIn)
Weitere Verfasser: Gray, Julie E
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2009
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Nucleotides NAD 0U46U6E8UK Niacinamide 25X51I8RD4 NADP 53-59-8 Poly(ADP-ribose) Polymerases EC 2.4.2.30 mehr... Phosphotransferases (Alcohol Group Acceptor) EC 2.7.1.- NAD kinase EC 2.7.1.23 DNA-Directed DNA Polymerase EC 2.7.7.7 NADP phosphatase EC 3.1.3.- Nucleotidases Nicotinamidase EC 3.5.1.19
Beschreibung
Zusammenfassung:To investigate the proposed role for NAD metabolism in regulating seed dormancy, NAD metabolites and associated enzyme activities were analysed in seed of Arabidopsis thaliana ecotypes ranging from Col-0, which has low seed dormancy, to Cvi, which is highly dormant. Seed poly(ADP-ribosyl)ation levels did not correlate well with the depth of seed dormancy but did correlate with the sensitivity of germination to the DNA damaging agent MMS. Cvi seed had relatively high NAD and low NADP levels compared with the less dormant ecotypes and the NAD : NADP ratios correlated well with dormancy. The activity of NAD kinase was relatively low, and NADP phosphatase was relatively high in dormant Cvi seed, indicating that these enzymes may be involved in controlling the NAD : NADP ratio. Dormant fresh Cvi and nondormant after-ripened Cvi seeds were used to investigate further. Measurement of reduced and oxidised pyridine nucleotides indicated that breaking of dormancy was associated with a reduction in NAD levels but not with an increase in NADP levels. It is proposed that poly(ADP-ribose) polymerase is involved in protecting the seed from genotoxic stress, whereas the level of NAD affects the depth of dormancy, perhaps by enhancing abscisic acid (ABA) synthesis
Beschreibung:Date Completed 06.02.2009
Date Revised 29.01.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/j.1469-8137.2008.02641.x