Involvement of phospholipase D and phosphatidic acid in the light-dependent up-regulation of sorghum leaf phosphoenolpyruvate carboxylase-kinase
Monreal, JA; López-Baena, FJ; Vidal, J; Echevarría, C; García-Mauriño, S
HERO ID
1454073
Reference Type
Journal Article
Year
2010
Language
English
PMID
| HERO ID | 1454073 |
|---|---|
| In Press | No |
| Year | 2010 |
| Title | Involvement of phospholipase D and phosphatidic acid in the light-dependent up-regulation of sorghum leaf phosphoenolpyruvate carboxylase-kinase |
| Authors | Monreal, JA; López-Baena, FJ; Vidal, J; Echevarría, C; García-Mauriño, S |
| Journal | Journal of Experimental Botany |
| Volume | 61 |
| Issue | 10 |
| Page Numbers | 2819-2827 |
| Abstract | The photosynthetic phosphoenolpyruvate carboxylase (C(4)-PEPC) is regulated by phosphorylation by a phosphoenolpyruvate carboxylase kinase (PEPC-k). In Digitaria sanguinalis mesophyll protoplasts, this light-mediated transduction cascade principally requires a phosphoinositide-specific phospholipase C (PI-PLC) and a Ca(2+)-dependent step. The present study investigates the cascade components at the higher integrated level of Sorghum bicolor leaf discs and leaves. PEPC-k up-regulation required light and photosynthetic electron transport. However, the PI-PLC inhibitor U-73122 and inhibitors of calcium release from intracellular stores only partially blocked this process. Analysis of [(32)P]phosphate-labelled phospholipids showed a light-dependent increase in phospholipase D (PLD) activity. Treatment of leaf discs with n-butanol, which decreases the formation of phosphatidic acid (PA) by PLD, led to the partial inhibition of the C(4)-PEPC phosphorylation, suggesting the participation of PLD/PA in the signalling cascade. PPCK1 gene expression was strictly light-dependent. Addition of neomycin or n-butanol decreased, and a combination of both inhibitors markedly reduced PPCK1 expression and the concomitant rise in PEPC-k activity. The calcium/calmodulin antagonist W7 blocked the light-dependent up-regulation of PEPC-k, pointing to a Ca(2+)-dependent protein kinase (CDPK) integrating both second messengers, calcium and PA, which were shown to increase the activity of sorghum CDPK. |
| Doi | 10.1093/jxb/erq114 |
| Pmid | 20410319 |
| Wosid | WOS:000278692200024 |
| Is Certified Translation | No |
| Dupe Override | No |
| Comments | Source: Web of Science WOS:000278692200024 |
| Is Public | Yes |
| Language Text | English |
| Keyword | Ca(2+)-dependent protein kinase; phosphatidic acid; phosphoenolpyruvate carboxylase; phosphoenolpyruvate carboxylase kinase; phospholipase C; phospholipase D; Sorghum bicolor |