Please use this identifier to cite or link to this item:
logo share SHARE logo core CORE BASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE

Genetic and isotope ratio mass spectrometric evidence for the occurrence of starch degradation and cycling in illuminated Arabidopsis leaves

AuthorsBaslam, Marouane CSIC ORCID; Baroja-Fernández, Edurne CSIC ORCID CVN ; Ricarte-Bermejo, A. ; Sánchez-López, Ángela María CSIC ORCID ; Aranjuelo, Iker CSIC ORCID ; Bahaji, Abdellatif CSIC ORCID ; Muñoz Pérez, Francisco José CSIC ORCID ; Almagro, Goizeder CSIC ORCID ; Pujol, Pablo; Galarza, Regina; Teixidor, Pilar; Pozueta Romero, Javier CSIC ORCID
Issue Date2-Feb-2017
PublisherPublic Library of Science
CitationPLoS ONE 12(2): e0171245 (2017)
AbstractAlthough there is a great wealth of data supporting the occurrence of simultaneous synthesis and breakdown of storage carbohydrate in many organisms, previous 13CO2 pulse-chase based studies indicated that starch degradation does not operate in illuminated Arabidopsis leaves. Here we show that leaves of gwd, sex4, bam4, bam1/bam3 and amy3/isa3/lda starch breakdown mutants accumulate higher levels of starch than wild type (WT) leaves when cultured under continuous light (CL) conditions. We also show that leaves of CL grown dpe1 plants impaired in the plastidic disproportionating enzyme accumulate higher levels of maltotriose than WT leaves, the overall data providing evidence for the occurrence of extensive starch degradation in illuminated leaves. Moreover, we show that leaves of CL grown mex1/pglct plants impaired in the chloroplastic maltose and glucose transporters display a severe dwarf phenotype and accumulate high levels of maltose, strongly indicating that the MEX1 and pGlcT transporters are involved in the export of starch breakdown products to the cytosol to support growth during illumination. To investigate whether starch breakdown products can be recycled back to starch during illumination through a mechanism involving ADP-glucose pyrophosphorylase (AGP) we conducted kinetic analyses of the stable isotope carbon composition (δ13C) in starch of leaves of 13CO2 pulsed-chased WT and AGP lacking aps1 plants. Notably, the rate of increase of δ13C in starch of aps1 leaves during the pulse was exceedingly higher than that of WT leaves. Furthermore, δ13C decline in starch of aps1 leaves during the chase was much faster than that of WT leaves, which provides strong evidence for the occurrence of AGP-mediated cycling of starch breakdown products in illuminated Arabidopsis leaves.
Publisher version (URL)
Appears in Collections:(IDAB) Artículos

Files in This Item:
File Description SizeFormat
illuminated_arabidopsis_Baslam.pdf1,04 MBAdobe PDFThumbnail
Show full item record
Review this work

PubMed Central

checked on Jan 4, 2022


checked on Jan 12, 2022


checked on Jan 11, 2022

Page view(s)

checked on Jan 17, 2022


checked on Jan 17, 2022

Google ScholarTM




Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.