A5003222186- Microtubule and mitosis dynamics
- Protist diversity and phylogeny
- Genetic and Kidney Cyst Diseases
- Micro and Nano Robotics
- Photosynthetic Processes and Mechanisms
- Genomics and Chromatin Dynamics
- Cell Image Analysis Techniques
- Cellular Mechanics and Interactions
- DNA Repair Mechanisms
- Microbial Community Ecology and Physiology
- Algal biology and biofuel production
- RNA Research and Splicing
- Nuclear Structure and Function
- Gene Regulatory Network Analysis
- Mitochondrial Function and Pathology
- Immunodeficiency and Autoimmune Disorders
- Marine Ecology and Invasive Species
- Planarian Biology and Electrostimulation
- Autoimmune Bullous Skin Diseases
- Renal and related cancers
- Slime Mold and Myxomycetes Research
- Urticaria and Related Conditions
- Biocrusts and Microbial Ecology
- Interstitial Lung Diseases and Idiopathic Pulmonary Fibrosis
- Chromosomal and Genetic Variations
University of California, San Francisco
2016-2025
Marine Biological Laboratory
2010-2025
Chan Zuckerberg Initiative (United States)
2021-2022
Mission Bio (United States)
2013-2021
Universidad Católica de Santa Fe
2019
State Street (United States)
2018
New York University
2017
Joint Genome Institute
2007
Institut de Biologie Physico-Chimique
2007
Sorbonne Université
2007
Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It model system for studying chloroplast-based photosynthesis, as well the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited common ancestor animals, but lost in plants. We sequenced ∼120-megabase nuclear genome performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated...
Background: Structural studies of fixed cells have revealed that interphase chromosomes are highly organized into specific arrangements in the nucleus, and led to a picture nucleus as static structure with immobile held positions, an impression apparently confirmed by recent photobleaching studies. Functional chromosome behavior, however, suggest many essential processes, such recombination, require move around within nucleus.Results: To reconcile these contradictory views, we exploited...
To gain insight into the process of mitochondrial transmission in yeast, we directly labeled proteins and DNA (mtDNA) observed their fate after fusion two cells. this end, haploid cells opposite mating type were with different fluorescent dyes by fluorescence microscopy Parental protein markers rapidly redistributed colocalized throughout zygotes, indicating that during mating, parental mitochondria fuse contents intermix, consistent results previously obtained a single parentally derived...
A central question in cell biology is how cells determine the size of their organelles. Flagellar length control a convenient system for studying organelle regulation. Mechanistic models proposed flagellar regulation have been constrained by assumption that flagella are static structures once they assembled. However, recent work has shown dynamic and constantly turning over. We determined this turnover occurs at tips, assembly portion mediated intraflagellar transport (IFT). Blocking IFT...
Position-effect variegation (PEV) describes the stochastic transcriptional silencing of a gene positioned adjacent to heterochromatin. Using FISH, we have tested whether variegated expression eye-color brown in Drosophila is influenced by its nuclear localization. In embryonic nuclei, heterochromatic insertion at locus always spatially isolated from other However, during larval development this physically associates with regions on same chromosome manner. These observations indicate that...
In addition to the popular method of fluorescent protein fusion, live cell imaging has now seen more and application epitope tags. The small size these tags may reduce functional perturbation enable signal amplification. To address their background issue, we adapt self-complementing split proteins as for labelling. two tags, GFP11 sfCherry11 are derived from eleventh β-strand super-folder GFP sfCherry, respectively. FP11-tags enables a cost-effective scalable way insert them into endogenous...
AbstractFirst paragraph (this article has no abstract) For well over 100 years, cell biologists have been wondering what determines the size of cells. In modern times, we know all molecules that control cycle and division, but still do not understand how is determined. To check whether biology made any inroads on this age-old question, BMC Biology asked several heavyweights in field to tell us they think controlled, drawing a range different types. The essays collection address two related...
Model organisms are widely used in research as accessible and convenient systems to study a particular area or question biology. Traditionally only handful of have been studied, but modern tools enabling researchers extend the set model include less-studied more unusual systems. This Forum highlights range 'non-model organisms' emerging for tackling questions across whole spectrum biology (and beyond), opportunities challenges, outlook future.
Chromosome movements and spindle dynamics were visualized in living cells of the budding yeast Saccharomyces cerevisiae . Individual chromosomal loci detected by expression a protein fusion between green fluorescent (GFP) Lac repressor, which bound to an array operator binding sites integrated into chromosome. Spindle microtubules GFP Tub1, major alpha tubulin. elongation chromosome separation exhibited biphasic kinetics, centromeres separated before telomeres. Budding did not exhibit...
In the developing mouse embryo, leftward fluid flow on ventral side of node determines left-right (L-R) asymmetry. However, mechanism by which rotational movement cilia can generate a unidirectional remains hypothetical. Here we have addressed this question motion and morphological analyses dynamic model experiments. We found that stand, not perpendicular to surface, but tilted posteriorly. further confirmed such posterior tilt produce in These results strongly suggest L-R asymmetry is...
We have analyzed the progressive changes in spatial distribution of telomeres during meiosis using three-dimensional, high resolution fluorescence microscopy. Fixed meiotic cells maize (Zea mays L.) were subjected to situ hybridization under conditions that preserved chromosome structure, allowing identification stage-dependent telomere arrangements. found nuclei at last somatic prophase before exhibit a nonrandom, polarized organization resulting loose grouping telomeres. Quantitative...
Flagellar length regulation provides a simple model system for addressing the general problem of organelle size control. Based on systems-level analysis flagellar dynamics, we have proposed mechanism control in which is set by balance continuous assembly and disassembly. The proposes that rate dependent due to inherent dependence intraflagellar transport, whereas disassembly independent, such two rates can only reach point at single length. In this report, test theoretical using three...
The important role that cilia and flagella play in human disease creates an urgent need to identify genes involved ciliary assembly function. strong specific induction of flagellar-coding during flagellar regeneration Chlamydomonas reinhardtii suggests transcriptional profiling such cells would reveal new flagella-related genes. We have conducted a genome-wide analysis RNA transcript levels by using maskless photolithography method-produced DNA oligonucleotide microarrays with unique probe...
Specific interactions of chromatin with the nuclear envelope (NE) in early embryos Drosophila melanogaster have been mapped and analyzed. Using fluorescence situ hybridization, three-dimensional positions 42 DNA probes, primarily to chromosome 2L, nuclei intact embryos, revealing five euchromatic two heterochromatic regions associated NE. These results predict that there are approximately 15 NE contacts per arm, which delimit large loops 1-2 Mb. association sites do not strictly correlate...
The assembly and maintenance of eukaryotic flagella are regulated by intraflagellar transport (IFT), the bidirectional traffic IFT particles (recently renamed trains) within flagellum. We previously proposed balance-point length control model, which predicted that frequency train should decrease as a function flagellar length, thus modulating length-dependent rate. However, this model was challenged differential interference contrast microscopy observation is independent. Using total...
The dynamics by which homologous chromosomes pair is currently unknown. Here, we use fluorescence in situ hybridization combination with three-dimensional optical microscopy to show that pairing of the somatic chromosome arm 2L Drosophila occurs independent initiation at discrete loci rather than a processive zippering sites along length chromosome. By evaluating frequencies 11 on over several timepoints during embryonic development, all are paired very early within 13 h after egg...
Bud, This Mitochondrion's for You How is organelle size adjusted to be appropriate cell size? Rafelski et al. (p. 822 ) used a quantitative method measuring mitochondria in living budding yeast cells and found that rather than using the apparently simplest mechanism of dividing organelles equally among mother daughter cells, mitochondrial level bud, independent mother's own content, size, or age.
Gradients of diffusible long-range attractant and repellent proteins have been proposed to guide growing axons during nervous system development, but such gradients never visualized directly. In the embryonic spinal cord, commissural pioneer a circumferential trajectory floor plate at ventral midline directed by secreted netrin family. chick cord netrin-1 mRNA is expressed cells netrin-2 neural epithelial cells. Antibodies two netrins reveal gradient protein directly in path axons. The...