A fundamental characteristic of eukaryotic cells is the presence of membrane-bound compartments and membrane transport pathways in which the Golgi complex plays a central role in the selective processing, sorting, and secretion of proteins. The parasitic protozoan Giardia lamblia belongs to the earliest identified lineage among eukaryotes and therefore offers unique insight into the progression from primitive to more complex eukaryotic cells. Here, we report that Giardia trophozoites undergo a developmental induction of Golgi enzyme activities, which correlates with the appearance of a morphologically identifiable Golgi complex, as they differentiate to cysts. Prior to this induction, no morphologically or biochemically identifiable Golgi complex exists within nonencysting cells. Remarkably, protein secretion in both nonencysting and encysting trophozoites is inhibited by brefeldin A, and brefeldin A-sensitive membrane association of ADP-ribosylation factor and -COP is observed. These results suggest that the secretory machinery of Giardia resembles that of higher eukaryotes despite the absence of a Golgi complex in nonencysting trophozoites. These findings have implications both for defining the minimal machinery for protein secretion in eukaryotes and for examining the biogenesis of Golgi structure and function.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				E. V. Elias, R. Quiroga, N. Gottig, H. Nakanishi, T. E. Nash, A. Neiman, and H. D. Lujan Characterization of SNAREs Determines the Absence of a Typical Golgi Apparatus in the Ancient Eukaryote Giardia lamblia J. Biol. Chem., December 19, 2008; 283(51): 35996 - 36010. [Abstract] [Full Text] [PDF]

				D. M. Ratner, J. Cui, M. Steffen, L. L. Moore, P. W. Robbins, and J. Samuelson Changes in the N-Glycome, Glycoproteins with Asn-Linked Glycans, of Giardia lamblia with Differentiation from Trophozoites to Cysts Eukaryot. Cell, November 1, 2008; 7(11): 1930 - 1940. [Abstract] [Full Text] [PDF]

				H. G. Morrison, A. G. McArthur, F. D. Gillin, S. B. Aley, R. D. Adam, G. J. Olsen, A. A. Best, W. Z. Cande, F. Chen, M. J. Cipriano, et al. Genomic Minimalism in the Early Diverging Intestinal Parasite Giardia lamblia Science, September 28, 2007; 317(5846): 1921 - 1926. [Abstract] [Full Text] [PDF]

				J. B. Dacks and M. C. Field Evolution of the eukaryotic membrane-trafficking system: origin, tempo and mode J. Cell Sci., September 1, 2007; 120(17): 2977 - 2985. [Abstract] [Full Text] [PDF]

				N. Gottig, E. V. Elias, R. Quiroga, M. J. Nores, A. J. Solari, M. C. Touz, and H. D. Lujan Active and Passive Mechanisms Drive Secretory Granule Biogenesis during Differentiation of the Intestinal Parasite Giardia lamblia J. Biol. Chem., June 30, 2006; 281(26): 18156 - 18166. [Abstract] [Full Text] [PDF]

				S. Stefanic, D. Palm, S. G. Svard, and A. B. Hehl Organelle Proteomics Reveals Cargo Maturation Mechanisms Associated with Golgi-like Encystation Vesicles in the Early-diverged Protozoan Giardia lamblia J. Biol. Chem., March 17, 2006; 281(11): 7595 - 7604. [Abstract] [Full Text] [PDF]

				D.-D. Xin, J.-F. Wen, D. He, and S.-Q. Lu Identification of a Giardia krr1 Homolog Gene and the Secondarily Anucleolate Condition of Giaridia lamblia Mol. Biol. Evol., March 1, 2005; 22(3): 391 - 394. [Abstract] [Full Text] [PDF]

				C. D. Karr and E. L. Jarroll Cyst wall synthase: N-acetylgalactosaminyltransferase activity is induced to form the novel N-acetylgalactosamine polysaccharide in the Giardia cyst wall Microbiology, May 1, 2004; 150(5): 1237 - 1243. [Abstract] [Full Text] [PDF]

				M. Marti, A. Regos, Y. Li, E. M. Schraner, P. Wild, N. Muller, L. G. Knopf, and A. B. Hehl An Ancestral Secretory Apparatus in the Protozoan Parasite Giardia intestinalis J. Biol. Chem., June 27, 2003; 278(27): 24837 - 24848. [Abstract] [Full Text] [PDF]

				M. Marti, Y. Li, E. M. Schraner, P. Wild, P. Kohler, and A. B. Hehl The Secretory Apparatus of an Ancient Eukaryote: Protein Sorting to Separate Export Pathways Occurs Before Formation of Transient Golgi-like Compartments Mol. Biol. Cell, April 1, 2003; 14(4): 1433 - 1447. [Abstract] [Full Text] [PDF]

				M. C. Touz, H. D. Lujan, S. F. Hayes, and T. E. Nash Sorting of Encystation-specific Cysteine Protease to Lysosome-like Peripheral Vacuoles in Giardia lamblia Requires a Conserved Tyrosine-based Motif J. Biol. Chem., February 14, 2003; 278(8): 6420 - 6426. [Abstract] [Full Text] [PDF]

				J. G. Ellis IV, M. Davila, and R. Chakrabarti Potential Involvement of Extracellular Signal-regulated Kinase 1 and 2 in Encystation of a Primitive Eukaryote, Giardia lamblia. STAGE-SPECIFIC ACTIVATION AND INTRACELLULAR LOCALIZATION J. Biol. Chem., January 10, 2003; 278(3): 1936 - 1945. [Abstract] [Full Text] [PDF]

				M. C. Touz, N. Gottig, T. E. Nash, and H. D. Lujan Identification and Characterization of a Novel Secretory Granule Calcium-binding Protein from the Early Branching Eukaryote Giardia lamblia J. Biol. Chem., December 20, 2002; 277(52): 50557 - 50563. [Abstract] [Full Text] [PDF]

				N. Iwabe and T. Miyata Kinesin-Related Genes from Diplomonad, Sponge, Amphioxus, and Cyclostomes: Divergence Pattern of Kinesin Family and Evolution of Giardial Membrane-Bounded Organella Mol. Biol. Evol., September 1, 2002; 19(9): 1524 - 1533. [Abstract] [Full Text] [PDF]

				J. B. Dacks and W. F. Doolittle Novel syntaxin gene sequences from Giardia, Trypanosoma and algae: implications for the ancient evolution of the eukaryotic endomembrane system J. Cell Sci., April 15, 2002; 115(8): 1635 - 1642. [Abstract] [Full Text] [PDF]

				M. C. Touz, M. J. Nores, I. Slavin, C. Carmona, J. T. Conrad, M. R. Mowatt, T. E. Nash, C. E. Coronel, and H. D. Lujan The Activity of a Developmentally Regulated Cysteine Proteinase Is Required for Cyst Wall Formation in the Primitive Eukaryote Giardia lamblia J. Biol. Chem., March 1, 2002; 277(10): 8474 - 8481. [Abstract] [Full Text] [PDF]

				R. D. Adam Biology of Giardia lamblia Clin. Microbiol. Rev., July 1, 2001; 14(3): 447 - 475. [Abstract] [Full Text] [PDF]

				A. B. Hehl, M. Marti, and P. Köhler Stage-Specific Expression and Targeting of Cyst Wall Protein-Green Fluorescent Protein Chimeras in Giardia Mol. Biol. Cell, May 1, 2000; 11(5): 1789 - 1800. [Abstract] [Full Text]

				J. Shorter and G. Warren A Role for the Vesicle Tethering Protein, p115, in the Post-mitotic Stacking of Reassembling Golgi Cisternae in a Cell-free System J. Cell Biol., July 12, 1999; 146(1): 57 - 70. [Abstract] [Full Text] [PDF]

				S. K. Ghosh, J. Field, M. Frisardi, B. Rosenthal, Z. Mai, R. Rogers, and J. Samuelson Chitinase Secretion by Encysting Entamoeba invadens and Transfected Entamoeba histolytica Trophozoites: Localization of Secretory Vesicles, Endoplasmic Reticulum, and Golgi Apparatus Infect. Immun., June 1, 1999; 67(6): 3073 - 3081. [Abstract] [Full Text] [PDF]

				S. E. Francis, R. Banerjee, and D. E. Goldberg Biosynthesis and Maturation of the Malaria Aspartic Hemoglobinases Plasmepsins I and II J. Biol. Chem., June 6, 1997; 272(23): 14961 - 14968. [Abstract] [Full Text] [PDF]

				B. Soltys, M Falah, and R. Gupta Identification of endoplasmic reticulum in the primitive eukaryote Giardia lamblia using cryoelectron microscopy and antibody to Bip J. Cell Sci., January 7, 1996; 109(7): 1909 - 1917. [Abstract] [PDF]

				H. D. Luján, M. R. Mowatt, J. T. Conrad, B. Bowers, and T. E. Nash Identification of a Novel Giardia lamblia Cyst Wall Protein with Leucine-rich Repeats J. Biol. Chem., December 8, 1995; 270(49): 29307 - 29313. [Abstract] [Full Text] [PDF]