Dacks (Ph.D. Dalhousie University)
Department of Cell Biology
5-31 Medical Sciences Building
Phone: (780) 248-1493
Fax: (780) 492-0450 (fax)
- Canada Research Chair in Evolutionary Cell Biology
The membrane-trafficking system is a key characteristic of eukaryotes (humans, plants, yeast, etc.) and one of the defining features that separates us from bacteria at a cellular level. It is responsible for the proper movement and final location of most of the material in our cells. It underlies not only brain activity, and hormone secretion in humans, but healthy plant growth, as well as normal cellular activity in a diverse array of single-celled organisms important for our economy, our environment and our health. The pathogenic mechanisms of many parasites, such as the organisms causing malaria, primary amoebic meningoencephalitis and African sleeping sickness, are all underpinned by action of the membrane-trafficking system.
Evidence suggests that the membrane-trafficking system arose early-on in eukaryotic evolution, with the major protein families involved likely having been already present in our ancestors over one billion years ago. The innovation of an endomembrane system would have been crucial for early eukaryotes, allowing predation, surface remodelling and increased cell size.
The long-term goal of my research program is to understand the evolution and diversity of the eukaryotic membrane-trafficking system through genome sequencing, comparative genomics, phylogenetics and molecular cell biology.
Although evolutionary in nature, my research also provides insight into basic cell biology, parasitism and pathogenesis. By comparative genomics and evolutionary cell biology addressing organisms across from the breadth of eukaryotes (beyond yeast to man), core components of eukaryotic cellular systems are identified. This allows the development of models of cell biological mechanism that are valid for all eukaryotic cells. It is also possible to place in context some aspects that are unique to a particular model system. Features that are unique, when found in parasitic protistan pathogens, may represent potential therapeutic targets.
Two interconnected lines of research are currently on-going in my lab:
Origin and evolution of the membrane trafficking system. Detailed evolutionary studies of individual protein families (eg. SNAREs, vesicle coats) can reveal important information about the specific history of that membrane-trafficking machinery and about the membrane-trafficking system in general. Such studies have thus far demonstrated ancient complexity in the trafficking system. An immediate focus in the lab is to investigate the secretory system and the Golgi apparatus, the molecular evolution of which have been relatively unexplored.
Genomes and relationships of protists. Genomics has revolutionized the way that we think about both evolutionary and medical questions. The lab is currently involved in several international sequencing projects of protistan genomes to examine their membrane trafficking apparatus (Emiliania huxleyi, Guillardia theta, Bigelowiella natans, Monocercomonoides sp. Trimastix pyriformis), having just been involved in the successful publication of the Naegleria gruberi genome! The information from these projects provides insight into the biology of the organisms themselves as well as contributing data for molecular evolutionary studies.
Naegleria gruberi as an amoeba and flagellate
Pictures from http://genome.jgi-psf.org/Naegr1/Naegr1.home.html
Selected publications (** denotes corresponding authorship, underline denotes Dacks Lab trainee)
“Multivesicular bodies in the enigmatic amoeboflagellate Breviata anathema and the evolution of ESCRT 0” E. Herman, G. Walker, M. van der Giezen and J. B. Dacks** (2011) Journal of Cell Science 124: 613-621.
“Eukaryotic systematics: a 2011 user’s guide for cell biologists and parasitologists” G. Walker, A. Schlacht, R. Dorell and J. B. Dacks** (2011) Parasitology. Feb 15:1-26.
“Golgi Evolution” M. J. Klute, P. Melançon and J. B. Dacks** (2011) in “The Golgi”, G. Warren and J. Rothman eds, Cold Spring Harbor Press: also listed as Cold Spring Harb Perspect Biol. 2011 Jun 6. Pii: cshperspect.a007849v1. doi: 10.1101/cshperspect.a007849.
“The genome of the amoeboflagellate Naegleria gruberi suggests a complex ancestral eukaryote.” L. Fritz-Laylin, S. Prochnick, M. Ginger, J. B. Dacks, M. L. Carpenter, M. C. Field, A. Kuo, A. Paredez, J. Chapman, J. Pham, S. Shu, R. Neupane, M. Cipriano, J. Mancuso, H. Tu, A. Salamov, E. Lindquist, H. Shapiro, S. Lucas, I. V. Grigoriev, W. Z. Cande, C. Fulton, D. S. Rokhsar, S. C. Dawson. (2010) Cell 140: 631-642.
“Arf3 is activated selectively by BIGs at the trans-Golgi network.” F. Manolea, J. Chun, D. Chen, I. Clarke, N. Summerfeldt, J. B. Dacks and P. Melançon (2010) Mol Biol Cell. Jun;21(11):1836-49. Epub 2010 Mar 31.
“Comparative analysis of plant genomes allows the definition of the “Phytolongins”: a novel non-SNARE longin domain protein family.” M. Vedovato, V. Rossi, J.B. Dacks** and F. Filippini (2009) BMC Genomics 10:510.
“Evolution and diversity of the Golgi body.” K. Mowbrey and J.B. Dacks** (2009) FEBS Letters 583(23):3738-45.
“Yarrowia lipolytica uses a paralog of the peroxisome biogenesis factor Pex3p as the peroxisomal receptor for class V myosin.” J. Chang, F. Mast, D. Rachubinski, G.A. Eitzen, J. B. Dacks, R.A. Rachubinski (2009) Journal of Cell Biology Oct 19;187(2):233-46.
“Phylogenomic analyses support the monophyly of Excavata and resolve relationships among eukaryotic “supergroups.” V. Hampl, L. Hug, J. Leigh, J.B. Dacks, F.B. Lang, A.G.B. Simpson and A.J. Roger (2009) Proceedings of the National Academy of Sciences USA 106(10):3859-64.
“First and last ancestors: reconstructing evolution of the endomembrane system with ESCRTs, vesicle coat proteins, and nuclear pore complexes.” M. C. Field and J. B. Dacks (2009) Current Opinions in Cell Biology. 21: 1-10.
“Repeated secondary loss of adaptin complex genes in the Apicomplexa.” W.D. Nevin and J.B. Dacks** (2009) Parasitology International 58: 86-94.
“Phylogeny of endocytic components yields insight into the process of non-endosymbiotic organelle evolution.” J.B. Dacks**, P.P. Poon, and M.C. Field (2008) Proc Nat Acad Sci USA 105 (2) 588-593.
“Evolution of the eukaryotic membrane-trafficking system: Origin, tempo and mode.” J.B. Dacks** and M. C. Field (2007) Journal of Cell Science 120 2977-2986.
“The genome sequence of the sexually transmitted pathogen Trichomonas vaginalis.” J.M. Carlton, R.P. Hirt, J.C. Silva, A.L. Delcher, M. Schatz, Q. Zhao, J.R. Wortman, S.L. Bidwell, U.C.M. Alsmark, S. Besteiro, T. Sicheritz-Ponten, C.J. Noel, J.B. Dacks, P.G. Foster, C. Simillion, Y. Van de Peer, D. Miranda-Saavedra, G.J. Barton, G.D. Westrop, S. Müller, D. Dessi, P.L. Fiori, Q. Ren, I. Paulsen, H. Zhang, F.D. Bastida-Corcuera, A. Simoes-Barbosa, M.T. Brown, R. D. Hayes, M. Mukherjee, C.Y. Okumura, R. Schneider, A.J. Smith, S. Vanacova, M. Villalvazo, B.J. Haas, M. Pertea, T. Feldblyum, T.R. Utterback, C-L Shu, K. Osoegawa, P.J. de Jong, I. Hrdy, L. Horvathova, Z. Zubacova, P. Dolezal, S.-B. Malik, J.M. Logsdon, Jr., K. Henze, A. Gupta, C.C. Wang, R.L. Dunne, J.A. Upcroft, P. Upcroft, O. White, S.L. Salzberg, P. Tang, C. Chiu, Y. Lee, T. M. Embley, G. H. Coombs, J. C. Mottram, J.Tachezy, C.M. Fraser-Liggett and P.J. Johnson (2007) Science 315 (5809): 207-212.
“Reconstructing the mosaic glycolytic pathway of the anaerobic eukaryote Monocercomonoides.” N.A. Liapounova, V. Hampl, P.M.K. Gordon, C.W. Sensen, L. Gedamu, J.B. Dacks** (2006) Eukaryotic Cell 5(12):2138-46.
“Evolution of filamentous plant pathogens: gene exchange across eukaryotic kingdoms.” T.A. Richards, J.B. Dacks, J.M. Jenkinson, C.R. Thornton, N.J. Talbot. (2006) Current Biology 16 (18): 1857-1864.
“Evidence for Golgi bodies in proposed 'Golgi-lacking' lineages.” J.B. Dacks**, L.A.M. Davis, Å.M. Sjögren, J.O. Andersson, A.J. Roger and W.F. Doolittle (2003) “Evidence for cryptic Golgi in proposed ‘Golgi-lacking’ lineages”. Proceedings of the Royal Society, B. Letters. Nov 7;270 Suppl 2: S168-71.
Dr. Maria Aguilar Gonzalez