Research Area: Cell Biology
I study chromosome movements during cell division. We try to understand the entire process of cell division, but concentrate on chromosome movements during anaphase.
During anaphase, chromosomes move slowly to a spindle pole at a speed near that of a tectonic plate. One simple question is: what produces the force that causes the chromosome to move poleward? All agree that the spindle fibre that extends between chromosome and pole contains microtubules, and that the fibre propels the chromosomes poleward, but there is no agreement on how this is done. Most concentrate on microtubules, but other components in spindle fibres include actin and myosin; no-one knows what the different components do. One way we studied this was to irradiate small portions of spindles using a focussed beam of ultraviolet light (a UV microbeam) or avisible-light laser microbeam; after irradiation we studied chromosome or spindle pole movement in the irradiated cells using video microscopy and we looked at the structure of the irradiated spot using confocal immunofluorescence microscopy and electron microscopy. Chromosomes moved normally after the UV severed both microtubules and actin (Forer et al., 2003; Sheykhani et al., 2013a), so we argue that chromosomes move because a spindle matrix propels the chromosome’s spindle fibre poleward (review in Johansen et al., 2011; Forer et al., 2015). We implicated actin and myosin in force production using inhibitors (e.g., Sheykhani et al., 2013b), and we identified titin, another muscle protein, in spindles (Fabian et al., 2007); thus the matrix might contain actin, myosin and titin. A graduate student developed an in vivo system in which chromosomes move rapidly to poles after she depolymerised all spindle microtubules. This also shows that something other than microtubules causes chromosomes to move (Fegaras and Forer, 2018).
In our most recent work we discovered a new spindle component present in all animal cells, elastic tethers (like bungee cords) that extend between all separating chromosomes in anaphase (Forer et al., 2017). We don’t really know yet what tethers do, but initial experiments indicate that tethers signal between separating chromosomes to regulate their velocities of motion (Sheykhani e al., 2017). We are trying to understand what tethers are made of and what they do.
Fabian et al. (2007). Journal of Cell Science 120: 2190-2204.
Fegaras and Forer (2018). Protoplasma 255: 1205–1224
Forer et al. (2003). Cell Motility and the Cytoskeleton 56: 173-192.
Forer et al. (2017) European Journal of Cell Biology 96 :504–514
Sheykhani et al. (2013a). Cytoskeleton 70: 241-259.
Sheykhani et al. (2013b). European J Cell Biol. 92: 175-186.
Sheykhani et al. (2017) Cytoskeleton 74:91–103
Rui Wang, Professor
Research Areas: signaling transduction, physiology, electrophysiology, vascular diseases, smooth muscle cells, endothelial dysfunction, cell proliferation, bioenergetics, insulin resistance, genetic and epigenetic regulation, hydrogen sulfide, gasotransmitters
Description: I am most interested in the metabolism and physiological functions of hydrogen sulfide (H2S), a gas molecule produced in a wide array of mammalian cells. Using a plethora of state-of-the art techniques capable of exploring gene editing, post-translational modifications of proteins, antioxidant and redox balance, cellular proliferation and repair, vascular contractility and blood pressure control, to whole animal behavior and health, my team examines the pathogenic causes and the therapeutic strategies for cardiovascular diseases, diabetic complications, respiratory and liver functions, aging and longevity.
Elizabeth Clare, Assistant Professor
Research areas: environmental DNA biodiversity monitoring, response of species to habitat change, bat biology, tropical biology, species interactions
Description: In our research group we are developing and applying novel technological approaches to monitor biodiversity, identify species interactions, and assess ecosystem level responses to changes so that effective predictions can be made about future events. We are particularly interested in how flexibility in species use of resources can make them resilient to environmental change.
Kohitij Kar, Assistant Professor
Incoming Assistant Professor (July 1, 2022)
Website: http://kohitij.com (lab website coming soon…)
Research Areas: Primate visual intelligence, primate in-vivo neurophysiology, visual object recognition, artificial intelligence, deep neural networks, visual cognition, chemogenetic perturbation
Description: My primary research interests lie at the intersection of visual neuroscience and artificial intelligence. My lab at York will study visual intelligence (in neurotypical and atypical populations), driven by AI-inspired hypotheses and using state-of the art visual neurophysiology in primates in an attempt to improve theories and models of such behavior.