Sugar Levels Modulate Sorbitol Dehydrogenase Expression In Maize.

dc.creatorde Sousa, Sylvia Morais
dc.creatorPaniago, Mário del Giúdice
dc.creatorArruda, Paulo
dc.creatorYunes, José Andrés
dc.date2008-Oct
dc.date2015-11-27T13:12:56Z
dc.date2015-11-27T13:12:56Z
dc.date.accessioned2018-03-29T01:07:01Z
dc.date.available2018-03-29T01:07:01Z
dc.identifierPlant Molecular Biology. v. 68, n. 3, p. 203-13, 2008-Oct.
dc.identifier0167-4412
dc.identifier10.1007/s11103-008-9362-0
dc.identifierhttp://www.ncbi.nlm.nih.gov/pubmed/18566893
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/197853
dc.identifier18566893
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1298086
dc.descriptionThe first step in sucrose use by maize kernels produces fructose, regardless of whether the initial reaction is catalyzed by an invertase or the reversible sucrose synthase. This fructose can enter subsequent metabolism via hexokinase, or in maize kernels, by a sorbitol dehydrogenase that reversibly converts fructose + NADH to sorbitol + NAD. High levels of SDH activity suggest that kernels synthesize considerable amounts of sorbitol, but the molecular mechanism and functional role for this process have remained equivocal. To gain insights on the role of sorbitol synthesis in maize endosperm we cloned and characterized the transcriptional control of the maize sorbitol dehydrogenase (Sdh1) gene. Data indicated that Sdh1 was essentially kernel- and endosperm-specific, with maximal expression at both the mRNA and enzyme activity levels during early kernel development. Expression was elevated in high-sugar mutants (sugary1, shrunken2), also by sugar injections, and was more pronounced when transfected tissues were incubated at low oxygen concentrations. Control of Sdh1 expression in our transient assays was largely dependent on the first intron of Sdh1. We speculate that SDH activity may represent an adaptation to the high-sugar/low-oxygen environment of the endosperm. Under these conditions, the NADH-dependent reduction of fructose to sorbitol would regenerate NAD[+], thus contributing to the maintenance of the redox and energy status of the cell.
dc.description68
dc.description203-13
dc.languageeng
dc.relationPlant Molecular Biology
dc.relationPlant Mol. Biol.
dc.rightsfechado
dc.rights
dc.sourcePubMed
dc.subjectGene Expression Regulation, Enzymologic
dc.subjectGene Expression Regulation, Plant
dc.subjectGenome, Plant
dc.subjectL-iditol 2-dehydrogenase
dc.subjectMolecular Sequence Data
dc.subjectRna, Messenger
dc.subjectRegulatory Sequences, Nucleic Acid
dc.subjectSorbitol
dc.subjectSucrose
dc.subjectTranscription, Genetic
dc.subjectZea Mays
dc.titleSugar Levels Modulate Sorbitol Dehydrogenase Expression In Maize.
dc.typeArtículos de revistas


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