INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
artículos
Título:
ORF-C4 from the early branching eukaryote Giardia lamblia displays characteristics of alpha-crystallin small heat shock proteins.
Autor/es:
NORES MJ; PRUCCA CG,; QUIROGA R; ELÍAS EV; CAVALLÍN L; PRICE AM; SAURA A,; CARRANZA PG; GOTTIG N; SOLARI AJ; LUJAN HD
Revista:
BIOSCIENCE REPORTS
Editorial:
Biochemical Society
Referencias:
Año: 2008
ISSN:
0144-8463
Resumen:
Giardia lamblia is a medically important protozoan parasite with a basal position in the eukaryotic lineage and an interesting model to understand evolution of biochemical events in eukaryotic cells. G. lamblia trophozoites undergo significant changes to survive outside the intestine of their host by differentiating into infective cysts. In this work, we characterize the previously identified gene Orf-C4 (Giardia lamblia open reading frame C4), considered specific of G. lamblia. It encodes a 22 kDa protein that assembles into high molecular mass complexes during the entire life cycle of the parasite. ORF-C4 localizes to the cytoplasm of trophozoites and cysts, and forms large spherical aggregates when overexpressed. ORF-C4 over-expression and down-regulation do not affect trophozoite viability; however, differentiation into cysts is slightly delayed when the expression of ORF-C4 is down-regulated. In addition, ORF-C4 protein expression is modified under specific stress-inducing conditions. Neither orthologous proteins nor conserved domains are found in databases by conventional sequence analysis of the predicted protein. However, ORF-C4 presents a region structurally similar to the á-crystallin domain of small heat shock proteins. Here, we show the potential role of ORF-C4 as a small chaperone involved in response to stress (including encystation) in G. lamblia.