The hyperstability and composition of Giardias ventral disc highlights the remarkable versatility of microtubule organelles

摘要: Giardia is a common protistan parasite that causes diarrheal disease worldwide. Motile trophozoites colonize the small intestine, attaching to villi with ventral disc, unique and complex microtubule (MT) organelle. Attachment host epithelium allows resist peristalsis during infection of gastrointestinal tract. Despite our emerging view complexity disc architecture, we are still in very preliminary stages understanding how specific structural elements contribute stability or generate forces for attachment. The large, dome-shaped, spiral MT array decorated microribbon-crossbridge protein complexes (MR-CB) extend upward into cytoplasm. To find additional disc-associated proteins (DAPs), used modified method biochemical fractionation high salt followed by shotgun proteomic analyses validation GFP-tagging. Using this conjunction an ongoing subcellular localization screen, identified 54 new DAPs. Of 87 DAPs confirmed date, localize only remainder structures including flagella, basal bodies, median body. Almost one third known lack any homology other eukaryotes another simply contain ankyrin repeat domains. Many regions groove region margin. Lastly, show singlet comprising hyperstable lacks dynamic instability, attribute these properties presence both novel as well conserved MAPs MIPs stabilize ciliary doublet triplet MTs.