A5006343762- Protist diversity and phylogeny
- Microtubule and mitosis dynamics
- Genetic and Kidney Cyst Diseases
- Ubiquitin and proteasome pathways
- Methane Hydrates and Related Phenomena
- Microbial Community Ecology and Physiology
- Photosynthetic Processes and Mechanisms
- Genomics and Phylogenetic Studies
- 14-3-3 protein interactions
- Glycosylation and Glycoproteins Research
- Cellular transport and secretion
- Histone Deacetylase Inhibitors Research
- Cystic Fibrosis Research Advances
- Evolution and Genetic Dynamics
- Metalloenzymes and iron-sulfur proteins
- Protein Structure and Dynamics
- Advanced Electron Microscopy Techniques and Applications
- Proteoglycans and glycosaminoglycans research
- Assisted Reproductive Technology and Twin Pregnancy
- Zebrafish Biomedical Research Applications
- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Heavy Metal Exposure and Toxicity
- Geology and Paleoclimatology Research
- Epigenetics and DNA Methylation
Instytut Biologii Doświadczalnej im. Marcelego Nenckiego
2015-2024
Polish Academy of Sciences
2015-2024
Cytoskeleton (United States)
2023
University of Georgia
2004-2013
The Ohio State University
2010
Georgia Institute of Technology
2008
J. Craig Venter Institute
2006
Centre de Recherche en Biologie cellulaire de Montpellier
2005
Centre National de la Recherche Scientifique
2005
Sine Institute
2005
The ciliate Tetrahymena thermophila is a model organism for molecular and cellular biology. Like other ciliates, this species has separate germline soma functions that are embodied by distinct nuclei within single cell. germline-like micronucleus (MIC) its genome held in reserve sexual reproduction. soma-like macronucleus (MAC), which possesses processed from of the MIC, center gene expression does not directly contribute DNA to progeny. We report here shotgun sequencing, assembly, analysis...
Cilia are ubiquitous eukaryotic organelles responsible for cellular motility and sensory functions. The ciliary axoneme is a microtubule-based cytoskeleton consisting of two central singlets nine outer doublet microtubules. Cryo-electron microscopy-based studies have revealed complex network inside the lumen both tubules composed microtubule-inner proteins (MIPs). However, functions most MIPs remain unknown. Here, we present single-particle cryo-EM-based analyses Tetrahymena thermophila...
Polyglutamylation of tubulin has been implicated in several functions microtubules, but the identification responsible enzyme(s) challenging. We found that neuronal polyglutamylase is a protein complex containing tyrosine ligase-like (TTLL) protein, TTLL1. TTLL1 member large family proteins with TTL homology domain, whose members could catalyze ligations diverse amino acids to tubulins or other substrates. In model protist Tetrahymena thermophila, two conserved types polyglutamylases were...
The in vivo significance of microtubule severing and the mechanisms governing its spatial regulation are not well understood. In Tetrahymena, a cell type with elaborate arrays, we engineered null mutations subunits microtubule-severing complex, katanin. We show that katanin activity is essential. net effect on polymer mass depends location. Although reduces destabilizes internal network microtubules, increases ciliary microtubules. also levels several types post-translational modifications...
Cilia are hairlike protrusions that project from the surface of eukaryotic cells and play key roles in cell signaling motility. Ciliary motility is regulated by conserved nexin-dynein regulatory complex (N-DRC), which links adjacent doublet microtubules regulates coordinates activity outer complexes. Despite its critical role cilia motility, assembly molecular basis mechanism poorly understood. Here, using cryo-electron microscopy conjunction with biochemical cross-linking integrative...
The genome of Tetrahymena thermophila contains 39 loci encoding NIMA-related kinases (NRKs), an extraordinarily large number for a unicellular organism. Evolutionary analyses grouped these sequences into several subfamilies, some which have orthologues in animals, whereas others are protist specific. When overproduced, NRKs three subfamilies caused rapid shortening cilia. Ultrastructural studies revealed that each NRK triggered ciliary resorption by distinct mechanism involved preferential...
Abstract Background The post-translational addition of the monosaccharide O-linked β- N -acetylglucosamine (O-GlcNAc) regulates activity a wide variety nuclear and cytoplasmic proteins. enzymes O-GlcNAc Transferase (Ogt) O-GlcNAcase (Oga) catalyze, respectively, attachment removal to target In adult mice, Ogt Oga attenuate response insulin by modifying several components signal transduction pathway. Complete loss ogt function, however, is lethal mouse embryonic stem cells, suggesting that...
Tubulin undergoes glutamylation, a conserved posttranslational modification of poorly understood function. We show here that in the ciliate Tetrahymena, most microtubule arrays contain glutamylated tubulin. However, length polyglutamyl side chain is spatially regulated, with longest chains present on ciliary and basal body microtubules. focused our efforts function glutamylation alpha-tubulin subunit. By site-directed mutagenesis, we all six glutamates C-terminal tail domain provide...
Dynein motors and regulatory complexes repeat every 96 nm along the length of motile cilia. Each contains three radial spokes, RS1, RS2, RS3, which transduct signals between central microtubules dynein arms. spoke has a distinct structure, but little is known about mechanisms assembly function individual spokes. In Chlamydomonas, calmodulin spoke-associated complex (CSC) composed FAP61, FAP91, FAP251 been linked to base RS2 RS3. We show that in Tetrahymena, loss either FAP61 or reduces cell...
Cilia beating is powered by the inner and outer dynein arms (IDAs ODAs). These multi-subunit macrocomplexes are arranged in two rows on each doublet along entire cilium length, except its distal end. To generate cilia beating, activity of ODAs IDAs must be strictly regulated locally interactions with arm-associated structures within ciliary unit coordinated globally time space between doublets axoneme. Here, we provide evidence a novel complex composed conserved WD-repeat proteins, Fap43p...
Cilia, essential motile and sensory organelles, have several compartments: the basal body, transition zone, middle distal axoneme segments. The segment accommodates key functions, including cilium assembly activities. While contains doublet microtubules (incomplete B-tubules fused to complete A-tubules), only A-tubule extensions, its existence requires coordination of microtubule length at nanometer scale. We show that three conserved proteins, two which are mutated in ciliopathy Joubert...
Ciliary beating requires the coordinated activity of numerous axonemal complexes. The protein composition and role radial spokes (RS), nexin links (N-DRC) dyneins (ODAs IDAs) is well established. However, how information transmitted from central apparatus to RS across other ciliary structures remains unclear. Here, we identify a complex comprising evolutionarily conserved proteins Ccdc96 Ccdc113, positioned parallel N-DRC forming connection between RS3, dynein g, N-DRC. Although Ccdc113 can...
Motile cilia are essential for propelling cells and moving fluids across tissues. The activity of axonemal dynein motors must be precisely coordinated to generate ciliary motility, but their regulatory mechanisms not well understood. tether head (T/TH) complex was hypothesized provide mechanical feedback during beating because it links the motor domains I1 doublet microtubule. Combining genetic biochemical approaches with cryoelectron tomography, we identified FAP44 FAP43 (plus...
In most eukaryotic cells, tubulin is subjected to posttranslational glutamylation, a conserved modification of unclear function. The glutamyl side chains form as branches the primary sequence glutamic acids in two biochemically distinct steps: initiation and elongation. length chain spatially controlled microtubule type specific. Here, we probe significance regulation vivo by overexpressing potent elongase enzyme, Ttll6Ap, Tetrahymena. Overexpression Ttll6Ap caused hyperelongation on...
ABSTRACT Plant and protozoan microtubules are selectively sensitive to dinitroanilines, which do not disrupt vertebrate or fungal microtubules. Tetrahymena thermophila is an abundant source of dinitroaniline-sensitive tubulin, we have modified the single T. α-tubulin gene create strains that solely express mutant in functional dimers. Previous research identified multiple mutations confer dinitroaniline resistance human parasite Toxoplasma gondii , when two these (L136F I252L) were...