INVESTIGADORES
NUSBLAT alejandro David
congresos y reuniones científicas
Título:
CARACTERIZACION DE UNA NUEVA ESTEROL C-22 DESATURASA DEL CILIADO TETRAHYMENA THERMOPHILA
Autor/es:
MARIA LUZ SANCHEZ; GARCÍA SIBURU, NICOLÁS; FRICSKA, ANNAMÁRIA; MALDONADO, LUCAS L.; GARGIULO, LAURA B.; B.C. NUDEL; A. D. UTTARO; A. D. NUSBLAT
Lugar:
Ciudad de Buenos Aires
Reunión:
Congreso; XXXIII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE PROTOZOOLOGÍA; 2022
Institución organizadora:
Sociedad Argentina de Protozoología
Resumen:
Sterols in eukaryotic cells play important roles inmodulating membrane fluidity and in cellsignaling and trafficking. During evolution, acombination of gene losses and acquisitions gaverise to an extraordinary diversity of sterols indifferent organisms. The sterol C-22 desaturaseidentified in plants and fungi as a cytochrome P450 monooxygenase evolved from the firsteukaryotic cytochrome P450 and was lost inmany lineages. Although the ciliate Tetrahymenathermophila desaturates sterols at the C-22position, no cytochrome P-450 orthologs arepresent in the genome. Here, we aim to identifythe genes responsible for the desaturation aswell as their probable origin. We used geneknockout and yeast heterologous expressionapproaches to identify two putative genes,retrieved from a previous transcriptomicanalysis, as sterol C-22 desaturases.Furthermore, we demonstrate usingbioinformatics and evolutionary analyses thatboth genes encode a novel type of sterol C-22desaturase that belongs to the large Fatty AcidHydroxylase/Desaturase superfamily, and thegenes originated by genetic duplication prior tofunctional diversification. These results stressthe widespread existence of non-homologousisofunctional enzymes among different lineagesof the tree of life as well as the suitability for theuse of T. thermophila as a valuable model toinvestigate the evolutionary process of largeenzyme families.