ORF-C4 from the early branching eukaryote Giardia lamblia displays characteristics of alpha-crystallin small heat shock proteinsBiosciences Report

NORES MJ; PRUCCA CG; QUIROGA R; ELÍAS EV; CAVALLÍN L; PRICE AM; SAURA A; CARRANZA PG; GOTTIG N; SOLARI AJ; LUJAN HD

PORTLAND PRESS LTD

Año: 2009 vol. 29 p. 25 - 25

Giardia lamblia is a medically important protozoan parasite with a basal position in the eukaryotic lineage and is an interesting model to explain the evolution of biochemical events in eukaryotic cells. G. lamblia trophozoites undergo significant changes in order to survive outside the intestine of their host by differentiating into infective cysts. In the present study, we characterize the previously identified Orf-C4 (G. lamblia open reading frame C4) gene, which is considered to be specific to 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 overexpression 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 unde