title: Study of the expression of carotenoid biosynthesis genes in wild-type and deregulated strains of Xanthophyllomyces dendrorhous (Ex.: Phaffia rhodozyma).
abstract: The expression, at the mRNA level, of carotenoid biosynthetic genes from Xanthophyllomyces dendrorhous was studied by RT-PCR. The experimental conditions for the RT-PCR assay were standardized to quantify the relative transcript levels of idi, crtE, crtYB and crtI genes. This work attempted to correlate astaxanthin production with the transcript levels of carotenogenic genes in a wild-type strain (UCD 67-385) and two overproducer deregulated strains (atxS1 and atxS2). At 3 day cultures, the wild-type strain contained higher transcript levels from the crtE and crtYB genes on minimal medium than on rich medium. Similarly, carotenoid production was higher on minimal medium than on rich medium. However, carotenoid production in the atxS1 and atxS2 strains was not correlated with the transcript level of carotenogenic genes under the same experimental conditions. This result suggests that there is not a linear relationship between carotenogenic transcript levels and carotenoid biosynthesis.
authors.affiliation: Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile.
authors.forename: Patricia
authors.initials: P
authors.lastname: Lodato
authors.forename: Jennifer
authors.initials: J
authors.lastname: Alcaíno
authors.forename: Salvador
authors.initials: S
authors.lastname: Barahona
authors.forename: Patricio
authors.initials: P
authors.lastname: Retamales
authors.forename: Antonio
authors.initials: A
authors.lastname: Jiménez
authors.forename: Víctor
authors.initials: V
authors.lastname: Cifuentes
mesh_terms: D001487:Basidiomycota / Q000235:genetics* / Q000378:metabolism; D003470:Culture Media; D018076:DNA, Complementary / Q000096:biosynthesis; D015966:Gene Expression Regulation, Fungal; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D024341:Xanthophylls; D019207:beta Carotene / Q000031:analogs & derivatives* / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D003470:Culture Media; D018076:DNA, Complementary; D012333:RNA, Messenger; D024341:Xanthophylls; D019207:beta Carotene; C005948:astaxanthine