Fecha/hora: 12/06/2024 14:28:13

Biblioteca(s): 	INIA Las Brujas.	
Fecha corriente: 	22/01/2020	
Fecha de la última actualización: 	24/02/2022	
Autoria: 	RODRIGO, M.J.; LADO, J.; ALÓS, E.; ALQUÉZAR, B.; DERY, O.; HIRSCHBERG, J.; ZACARÍAS, L.	
Afiliación: 	MARÍA JESÚS RODRIGO, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Spain; JOANNA LADO LINDNER, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Spain; ENRIQUETA ALÓS, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Spain; BERTA ALQUÉZAR, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Spain; Instituto de Biología Molecular y Celular de Plantas (IBMCP), UPV-CSIC, Spain; ORLY DERY, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel; JOSEPH HIRSCHBERG, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel; LORENZO ZACARÍAS, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Spain.	
Título: 	A mutant allele of &#950;-carotene isomerase (Z-ISO) is associated with the yellow pigmentation of the "pinalate" sweet orange mutant and reveals new insights into its role in fruit carotenogenesis.	
Año de publicación: 	2019	
Fuente/Imprenta: 	BMC Plant Biology, 4 November 2019, Volume 19, Issue 1, Article number 465. OPEN ACCESS. Doi: DOI: 10.1186/s12870-019-2078-2	
ISSN: 	1471-2229	
DOI: 	10.1186/s12870-019-2078-2	
Idioma: 	Inglés	
Notas: 	Article history: Received: 17 June 2019 / Accepted: 16 October 2019 / Published online: 4 November 2019.
Funding text: Financial support of the research grants AGL2012?34576 and AGL2015? 70218 (Ministerio Economía y Competitividad, Spain), and RTI2018-095131-BI00 (Ministerio Ciencia, Innovacion y Universidades, Spain). Work in the group of JH was supported by Israel Science Foundation Grant 850/13. MJR, LZ, JH and OD are members of Eurocaroten (COST_Action CA15136). MJR and LZ belong to CaRed (Spanish Carotenoid Network BIO2017?90877-REDT, Minis-terio de Ciencia, Innovación y Universidades, Spain). Authors acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).
Supplementary information accompanies this paper.	
Contenido: 	Abstract.
Background: Fruit coloration is one of the main quality parameters of Citrus fruit primarily determined by genetic factors. The fruit of ordinary sweet orange (Citrus sinensis) displays a pleasant orange tint due to accumulation of carotenoids, representing &#946;,&#946;-xanthophylls more than 80% of the total content. 'Pinalate' is a spontaneous bud mutant, or somatic mutation, derived from sweet orange 'Navelate', characterized by yellow fruits due to elevated proportions of upstream carotenes and reduced &#946;,&#946;-xanthophylls, which suggests a biosynthetic blockage at early steps of the carotenoid pathway. Results: To identify the molecular basis of 'Pinalate' yellow fruit, a complete characterization of carotenoids profile together with transcriptional changes in carotenoid biosynthetic genes were performed in mutant and parental fruits during development and ripening. 'Pinalate' fruit showed a distinctive carotenoid profile at all ripening stages, accumulating phytoene, phytofluene and unusual proportions of 9,15,9&#8242;-tri-cis- and 9,9&#8242;-di-cis-&#950;-carotene, while content of downstream carotenoids was significantly decreased. Transcript levels for most of the carotenoid biosynthetic genes showed no alterations in 'Pinalate'; however, the steady-state level mRNA of &#950;-carotene isomerase (Z-ISO), which catalyses the conversion of 9,15,9&#8242;-tri-cis- to 9,9&#8242;-di-cis-&#950;-carotene, was significantly reduced both in 'Pinalate' fruit and leaf tissues. Isolation of the 'Pinalate' Z-ISO genomic sequence identified a new allele with a single nucleotide insertion at the second exon, which generates an alternative splicing site that alters Z-ISO transcripts encoding non-functional enzyme. Moreover, functional assays of citrus Z-ISO in E.coli showed that light is able to enhance a non-enzymatic isomerization of tri-cis to di-cis-&#950;-carotene, which is in agreement with the partial rescue of mutant phenotype when 'Pinalate' fruits are highly exposed to light during ripening. Conclusion: A single nucleotide insertion has been identified in 'Pinalate' Z-ISO gene that results in truncated proteins. This causes a bottleneck in the carotenoid pathway with an unbalanced content of carotenes upstream to &#946;,&#946;-xanthophylls in fruit tissues. In chloroplastic tissues, the effects of Z-ISO alteration are mainly manifested as a reduction in total carotenoid content. Taken together, our results indicate that the spontaneous single nucleotide insertion in Z-ISO is the molecular basis of the yellow pigmentation in 'Pinalate' sweet orange and points this isomerase as an essential activity for carotenogenesis in citrus fruits. 
© 2019 The Author(s).	
Palabras-Clave: 	Carotenoid; GENE EXPRESSION; MUTANT; Pigmentation; PLATAFORMA AGROALIMENTOS; RIPENING; Zeta-carotene isomerase.	
Thesagro: 	CAROTENOIDES; CITRUS.	
Categoría del tema: 	F01 Cultivo	
URL: 	http://www.ainfo.inia.uy/digital/bitstream/item/14051/1/BMC-Plant-Pathology-2019-s12870-019-2078-2.pdf
https://bmcplantbiol.biomedcentral.com/track/pdf/10.1186/s12870-019-2078-2	
Registro original: 	INIA Las Brujas (LB)	
Ejemplares: 	LB - (102100-1) - PXI - AP - DD - PP/BMC Plant Biology/2019 -  -  - DIS