IAL 21557
INSTITUTO DE AGROBIOTECNOLOGIA DEL LITORAL
Unidad Ejecutora - UE
artículos
Título:
Proteolytic cleavage of Arabidopsis thaliana phospho enol pyruvate carboxykinase-1 modifies its allosteric regulation
Autor/es:
FIGUEROA, CARLOS M; ROJAS, BRUNO E; IGLESIAS, ALBERTO A; HARTMAN, MATÍAS D
Revista:
JOURNAL OF EXPERIMENTAL BOTANY
Editorial:
OXFORD UNIV PRESS
Referencias:
Año: 2020
ISSN:
0022-0957
Resumen:
Phosphoenolpyruvate carboxykinase (PEPCK) plays a crucial role in gluconeogenesis. In this work, we analyze theproteolysis of Arabidopsis thaliana PEPCK1 (AthPEPCK1) in germinating seedlings. We found that the amount ofAthPEPCK1 protein peaks at 24?48 h post-imbibition. Concomitantly, we observed shorter versions of AthPEPCK1,putatively generated by metacaspase-9 (AthMC9). To study the impact of AthMC9 cleavage on the kinetic and regulatoryproperties of AthPEPCK1, we produced truncated mutants based on the reported AthMC9 cleavage sites. TheΔ19 and Δ101 truncated mutants of AthPEPCK1 showed similar kinetic parameters and the same quaternary structureas the wild type. However, activation by malate and inhibition by glucose 6-phosphate were abolished in the Δ101mutant. We propose that proteolysis of AthPEPCK1 in germinating seedlings operates as a mechanism to adapt thesensitivity to allosteric regulation during the sink-to-source transition.
