Functional Characterization of Lysophosphatidylcholine: Acyl-CoA Acyltransferase Genes From Sunflower (Helianthus annuus L.)

Lysophosphatidylcholine acyltransferase (LPCAT, EC 2.3.1.23) is an evolutionarily conserved key enzyme in the Lands cycle that catalyzes acylation of lysophosphatidylcholine (LPC) to produce phosphatidylcholine (PC), the main phospholipid in cellular membranes. In this study, three LPCAT genes from...

Descripción completa

Detalles Bibliográficos
Autores: Mapelli Brahm, Ana, Sánchez Rodriguez, Rosario, Pan, Xue, Moreno Pérez, Antonio Javier, Garcés, Rafael, Martínez Force, Enrique, Weselake, Randall J., Salas Liñán, Joaquín Jesús, Venegas Calerón, Mónica
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/96070
Acceso en línea:https://hdl.handle.net/11441/96070
https://doi.org/10.3389/fpls.2020.00403
Access Level:acceso abierto
Palabra clave:Helianthus
LPCAT
desaturation
linoleate
lysophosphatidylcholine acyltransferase
oil synthesis
sunflower
Descripción
Sumario:Lysophosphatidylcholine acyltransferase (LPCAT, EC 2.3.1.23) is an evolutionarily conserved key enzyme in the Lands cycle that catalyzes acylation of lysophosphatidylcholine (LPC) to produce phosphatidylcholine (PC), the main phospholipid in cellular membranes. In this study, three LPCAT genes from sunflower were identified and the corresponding proteins characterized. These HaLPCAT genes encoded functionally active enzymes that were able to complement a deficient yeast mutant. Moreover, enzymatic assays were carried out using microsomal preparations of the yeast cells. When acyl specificities were measured in the forward reaction, these enzymes exhibited a substrate preference for unsaturated acyl-CoAs, especially for linolenoyl-CoA, while in the reverse reaction, linoleoyl or linolenoyl acyl groups were transferred from PC to acyl-CoA to a similar extent. Expression levels of LPCAT genes were studied revealing distinct tissue-specific expression patterns. In summary, this study suggests that the combined forward and reverse reactions catalyzed by sunflower LPCATs facilitate acyl-exchange between the sn-2 position of PC and the acyl-CoA pool. Sunflower LPCATs displayed different characteristics, which could point to different functionalities, favoring the enrichment of seed triacylglycerols (TAGs) with polyunsaturated fatty acid (PUFA)