INGEBI   02650
INSTITUTO DE INVESTIGACIONES EN INGENIERIA GENETICA Y BIOLOGIA MOLECULAR "DR. HECTOR N TORRES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
IDENTIFICATION AND CHARACTERIZATION OF AMP-ACTIVATED PROTEIN KINASE IN TRYPANOSOMA CRUZI
Autor/es:
TAMARA STERNLIEB; PATRICIO GENTA; ALEJANDRA C. SCHOIJET; MARÍA J. FIGUERAS
Lugar:
Buenos Aires
Reunión:
Congreso; XXVII Reunión Anual de la Sociedad Argentina de Protozoología; 2015
Institución organizadora:
Sociedad Argentina de Protozoología
Resumen:
The AMP-activated protein kinase (AMPK) is a heterotrimeric enzyme involved in maintaining energyhomeostasis in response to nutrient stress in many organisms. Sequence and structure of its subunitsmay change between organisms, but they maintain the same function. The subunit contains akinase domain as well as a regulatory domain that inhibits the enzyme in the absence of AMP. Thesubunit acts as a scaffold for the other components, while the subunit is thought to be involved inAMP binding. During the transition from the mammal host to the insect vector, Trypanosoma cruzisuffers nutritional stress from the absence of glucose in the insect?s midgut. The ability to respond tothis stress, allows the parasite to differentiate and survive. Recently, AMPK β and γ subunits havebeen identified in Trypanosoma brucei, and it was shown that they are involved in surface proteinexpression changes in response to nutritional stress. Nevertheless, the α subunit couldn?t be found.Using conserved domains and secondary structure analysis, we have been able to identify candidategenes for the catalytic subunit of both organisms, named TbAMPKα and TcAMPKα. On the otherhand, we have identified the genes corresponding to AMPK β and γ subunits in T. cruzi (TcAMPKβ andγ), which present significant sequence differences from human AMPK. These three gene sequenceswere all successfully expressed in E. coli attached to a GST tag. Subsequently, this will allow us topurify the recombinant proteins and perform different binding assays. Also, we generated transgenicepimastigotes lines overexpressing TcAMPKγ along with a hemagglutinin tag, which allowed us todetermine its co-localization with glycosomes through immunofluorescence assays. Among otherobjectives, we are trying to elucidate the effects of nutritional stress on the subunits localization andfunction by starvation assays.