A5034877269- Mitochondrial Function and Pathology
- Fungal and yeast genetics research
- Genetic Neurodegenerative Diseases
- Photosynthetic Processes and Mechanisms
- Microtubule and mitosis dynamics
- Genetics, Aging, and Longevity in Model Organisms
- Microbial Metabolic Engineering and Bioproduction
- Advanced Fluorescence Microscopy Techniques
- Ubiquitin and proteasome pathways
- Cellular Mechanics and Interactions
- Biotin and Related Studies
- Lipid metabolism and biosynthesis
- Metabolism and Genetic Disorders
- Endoplasmic Reticulum Stress and Disease
- Cardiomyopathy and Myosin Studies
- RNA and protein synthesis mechanisms
- Cellular transport and secretion
- ATP Synthase and ATPases Research
- Adipose Tissue and Metabolism
- Plant Reproductive Biology
- Cell Image Analysis Techniques
- Redox biology and oxidative stress
- Metabolism, Diabetes, and Cancer
- Peroxisome Proliferator-Activated Receptors
- Neuroscience and Neuropharmacology Research
Columbia University
2015-2024
Columbia University Irving Medical Center
2009-2024
University of Exeter
2022
Estación Experimental del Zaidín
2022
Shanghai Jiao Tong University
2022
Keio University
2022
Sanford Burnham Prebys Medical Discovery Institute
2022
Western University
2022
National Centre for Biological Sciences
2022
Heidelberg University
2022
Making the right contacts Contacts between endoplasmic reticulum (ER) and mitochondria mediate key physiological processes such as Ca 2+ exchange lipid biogenesis. wiIn yeast, ER are tethered by a complex of four proteins called ERMES. However, no functional orthologs these ERMES have been identified in metazoans. Hirabayashi et al. PDZD8 structural ortholog yeast protein MMM1 (see Perspective Lombardi Elrod). was found at ER-mitochondria contact sites required for tethering mammalian cells....
Previous studies indicate that two proteins, Mmm1p and Mdm10p, are required to link mitochondria the actin cytoskeleton of yeast for actin-based control mitochondrial movement, inheritance morphology. Both proteins integral outer membrane proteins. localizes punctate structures in close proximity DNA (mtDNA) nucleoids. We found Mdm10p exist a complex with Mdm12p, another protein morphology inheritance. This interpretation is based on observations 1) Mdm12p showed same localization as Mmm1p;...
The organization of the actin cytoskeleton plays a critical role in cell physiology motile and nonmotile organisms. Nonetheless, function based motor molecules, members myosin superfamily, is not well understood. Deletion MYO3, yeast gene encoding "classic" I, has no detectable phenotype. We used synthetic lethality screen to uncover genes whose functions might overlap with those MYO3 identified second 1 gene, MYO5. MYO5 shows 86 62% identity across non-motor regions. Both contain an amino...
Using fluorescent membrane potential sensing dyes to stain budding yeast, mitochondria are resolved as tubular organelles aligned in radial arrays that converge at the bud neck. Time-lapse fluorescence microscopy reveals region-specific, directed mitochondrial movement during polarized yeast cell growth and mitotic division. Mitochondria central region of mother move linearly towards bud, traverse neck, progress tip an average velocity 49 +/- 21 nm/sec. In contrast, peripheral display...
The Arp2/3 complex is implicated in actin polymerization-driven movement of Listeria monocytogenes . Here, we find that Arp2p and Arc15p, two subunits this complex, show tight, actin-independent association with isolated yeast mitochondria. colocalizes Consistent result, detect Arp2p-dependent formation clouds around mitochondria intact yeast. Cells bearing mutations ARP2 or ARC15 genes decreased velocities mitochondrial movement, loss all directed defects morphology. Finally, observe a...
Fluorescence loss in photobleaching experiments and analysis of mitochondrial function using superoxide redox potential biosensors revealed that mitochondria within individual yeast cells are physically functionally distinct. Mitochondria retained mother during cell division have a significantly more oxidizing higher levels compared to buds. Retention with occurs the same extent young older can account for age-associated decline total cellular as they age from 0 5 generations. Deletion...
Actin cables, bundles of actin filaments that align along the long axis budding yeast, are crucial for establishment cell polarity. We fused green fluorescent protein (GFP) to binding 140 (Abp140p) and visualized cable dynamics in living yeast. detected two populations cables: ( i ) bud-associated which extend from bud mother-bud axis, ii randomly oriented relatively short. Time-lapse imaging Abp140p–GFP revealed an apparent increase length cables. Analysis movement fiduciary marks on cables...
Transfer of mitochondria to daughter cells during yeast cell division is essential for viable progeny. The actin cytoskeleton required this process, potentially as a track direct mitochondrial movement into the bud. Sedimentation assays reveal two different components mitochondria–actin interactions: (1) binding protein(s) (mABP), peripheral outer membrane with ATP-sensitive activity, and (2) salt-inextractable, presumably integral, docking mABP on organelle. activity abolished by treatment...
Puf3p binds preferentially to messenger RNAs (mRNAs) for nuclear-encoded mitochondrial proteins. We find that localizes the cytosolic face of outer membrane. Overexpression PUF3 results in reduced respiratory activity and levels Pet123p, a protein encoded by Puf3p-binding mRNA. are during diauxic shift growth on nonfermentable carbon source, conditions stimulate biogenesis. These findings support role biogenesis through effects mRNA interactions. In addition, links mitochore, complex...
Using FM4-64 to label endosomes and Abp1p-GFP or Sac6p-GFP actin patches, we find that (1) colocalize with patches as they assemble at the bud cortex; (2) undergo linear, retrograde movement from buds toward mother cells; (3) interact disassemble FM4-64–labeled internal compartments. We also show flow of cables mediates patch movement. An Arp2/3 complex mutation decreases frequency cortical, nonlinear movements, but has no effect on velocity Rather, linear occurs same direction cables....
To identify the membrane regions through which yeast mitochondria import proteins from cytoplasm, we have tagged these with two different partly translocated precursor proteins. One of was bound to mitochondrial surface ATP-depleted and could subsequently be chased into upon addition ATP. The other intermediate irreversibly stuck across both membranes at protein sites. Upon subfraction mitochondria, intermediates cofractionated vesicles whose buoyant density between that inner outer...
Asymmetric growth and division of budding yeast requires the vectorial transport components organelles from mother to daughter cells. Time lapse video microscopy vital staining were used study motility events which result in partitioning mitochondria dividing yeast. We identified four different stages mitochondrial inheritance cycle: (1) align along mother-bud axis prior bud emergence G1 phase, following polarization actin cytoskeleton; (2) during S undergo linear, continuous polarized...
The budding yeast contains two type I myosins, Myo3p and Myo5p, with redundant functions. Deletion of both myosins results in growth defects, loss actin polarity polarized cell surface growth, accumulation intracellular membranes. Expression myc-tagged Myo5p myo3Δ myo5Δ cells fully restores wild-type characteristics. is localized as punctate, cortical structures enriched at sites growth. We find that latrunculin-A–induced depolymerization F-actin patches. Moreover, incubation 37°C transient...
Actin is one of the most abundant proteins in eukaryotic cells and a key component cytoskeleton. A range small molecules has emerged that interfere with actin dynamics by either binding to polymeric F-actin or monomeric G-actin stabilize destabilize filaments prevent their formation growth, respectively. Among these, latrunculins, which bind affect polymerization, are widely used as tools investigate actin-dependent cellular processes. Here, we report photoswitchable version latrunculin,...
Sedimentation assays were used to demonstrate and characterize binding of isolated yeast mitochondria phalloidin-stabilized F-actin. These actin-mitochondrial interactions are ATP sensitive, saturable, reversible, do not depend upon mitochondrial membrane potential. Protease digestion outer proteins or saturation myosin-binding sites on F-actin with the S1 subfragment skeletal myosin block binding. observations indicate that a protein (or proteins) surface mediates ATP-sensitive, reversible...