Work in the Green Lab is centered on the ribosome. The overall fidelity of protein synthesis appears to be limited by the action of the ribosome, which is the two-subunit macromolecular machine responsible for decoding and translating messenger RNAs (mRNAs) into protein in all organisms. Our work is divided into four general project areas. The longest-standing research area concerns the interactions of eubacterial ribosomes and release factors. The goal is to understand the mechanism of action of release factors on the ribosome. A second research area involves biochemical and structure/function studies of the miRNA pathway, particularly the mechanism of action of the Argonaute proteins and their interacting factors. A third area of work in the lab is centered around regulation of eukaryotic translation, specifically in understanding the mechanism behind various mRNA quality control pathways and the interactions of proteins therein, as well as with the ribosome. The newest area of rese...arch in the lab extends our strengths in ribosome biochemistry to characterize the translation status of the cell using the ribosome profiling. We are using this technique to better understand the role of several factors involved in eukaryotic and prokaryotic translation fidelity. view more

The Greider lab uses biochemistry to study telomerase and cellular and organismal consequences of telomere dysfunction. Telomeres protect chromosome ends from being recognized as DNA damage and chromosomal rearrangements. Conventional replication leads to telomere shortening, but telomere length is maintained by the enzyme telomerase. Telomerase is required for cells that undergo many rounds of divisions, especially tumor cells and some stem cells. The lab has generated telomerase null mice that are viable and show progressive telomere shortening for up to six generations. In the later generations, when telomeres are short, cells die via apoptosis or senescence. Crosses of these telomerase null mice to other tumor prone mice show that tumor formation can be greatly reduced by short telomeres. The lab also is using the telomerase null mice to explore the essential role of telomerase stem cell viability. Telomerase mutations cause autosomal dominant dyskeratosis congenita. People with ...this disease die of bone marrow failure, likely due to stem cell loss. The lab has developed a mouse model to study this disease. Future work in the lab will focus on identifying genes that induce DNA damage in response to short telomeres, identifying how telomeres are processed and how telomere elongation is regulated. view more

The Hey-Kyoung Lee Lab is interested in exploring the cellular and molecular changes that happen at synapses to allow memory storage. We use various techniques, including electrophysiological recording, biochemical and molecular analysis, and imaging, to understand the cellular and molecular changes that happen during synaptic plasticity.

Currently, we are examining the molecular and cellular mechanisms of global homeostatic synaptic plasticity using sensory cortices as model systems. In particular, we found that loss of vision elicits global changes in excitatory synaptic transmission in the primary visual cortex. Vision loss also triggers specific synaptic changes in other primary sensory cortices, which we postulate underlies sensory compensation in the blind. One of our main research goals is to understand the mechanisms underlying such cross-modal synaptic plasticity.

We are also interested in elucidating the events that occur in diseased brains. In collaboration with othe...r researchers, we are analyzing various mouse models of Alzheimer's disease, especially focusing on the possible alterations in synaptic plasticity mechanisms.
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Research in the Holland Lab focuses on the molecular mechanisms that control accurate chromosome distribution and the role that mitotic errors play in human health and disease. We use a combination of chemical biology, biochemistry, cell biology and genetically engineered mice to study pathways involved in mitosis and their effect on cell and organism physiology. One of our major goals is to develop cell and animal-based models to study the role of cell-division defects in genome instability and tumorigenesis.

Complexity in signaling networks is often derived from co-opting one set of molecules for multiple operations. Understanding how cells achieve such sophisticated processing using a finite set of molecules within a confined space--what we call the "signaling paradox"--is critical to biology and engineering as well as the emerging field of synthetic biology.

In the Inoue Lab, we have recently developed a series of chemical-molecular tools that allow for inducible, quick-onset and specific perturbation of various signaling molecules. Using this novel technique in conjunction with fluorescence imaging, microfabricated devices, quantitative analysis and computational modeling, we are dissecting intricate signaling networks.

In particular, we investigate positive-feedback mechanisms underlying the initiation of neutrophil chemotaxis (known as symmetry breaking), as well as spatio-temporally compartmentalized signaling of Ras and membrane lipids such as phosphoinositides. In parallel,... we also try to understand how cell morphology affects biochemical pathways inside cells. Ultimately, we will generate completely orthogonal machinery in cells to achieve existing, as well as novel, cellular functions. Our synthetic, multidisciplinary approach will elucidate the signaling paradox created by nature. view more

The Jeremy Nathans Laboratory is focused on neural and vascular development, and the role of Frizzled receptors in mammalian development. We use gene manipulation in the mouse, cell culture models, and biochemical reconstitution to investigate the relevant molecular events underlying these processes, and to genetically mark and manipulate cells and tissues. Current experiments are aimed at defining additional Frizzled-regulated processes and elucidating the molecular mechanisms and cell biologic results of Frizzled signaling within these various contexts. Complementing these areas of biologic interest, we have ongoing technology development projects related to genetically manipulating and visualizing defined cell populations in the mouse, and quantitative analysis of mouse visual system function.

Dr. Krishnan, Assistant Professor, received his Ph.D. in Biochemistry-Biotechnology from the University of Madras in 2008. He completed his postdoctoral fellowship in the Department of Pediatrics at the University of Alabama at Birmingham and Department of Pediatrics, University of Illinois at Chicago. After he worked as Research Associate in Department of Pediatrics at the University of South Florida, Dr. Krishnan joined the faculty at JHU in May 2018. His lab investigates the pathophysiology of Transfusion-associated Necrotizing Enterocolitis (TANEC) and Systemic Inflammatory Response Syndrome (SIRS) in premature infants who are at high risk of anemia and heavily transfused. Dr. Krishnan is dedicated to understanding the role of monocyte/macrophage in the neonate and investigating their inflammatory phenotype, function during anemia and/or RBC-transfusion associated NEC and SIRS.

Our research focuses on the biology of the peptidoglycan of Mycobacterium tuberculosis, the organism that causes tuberculosis, and Mycobacteroides abscessus, a related bacterium that causes opportunistic infections. We study basic mechanisms associated with peptidoglycan physiology but with an intent to leverage our findings to develop tools that will be useful in the clinic to treat mycobacterial infections.

Peptidoglycan is the exoskeleton of bacteria that not only provides structural rigidity and cell shape but also several vital physiological functions. Breaching this structure is often lethal to bacteria. We are exploring fundamental mechanisms by which bacteria synthesize and preserve their peptidoglycan. Although our lab uses genetic, biochemical and biophysical approaches to study the peptidoglycan, we pursue questions irrespective of the expertise required to answer those questions. It is through these studies that we identified synergy between two beta-lactam antibiotics a...gainst select mycobacteria. view more

The Caterina lab is focused on dissecting mechanisms underlying acute and chronic pain sensation. We use a wide range of approaches, including mouse genetics, imaging, electrophysiology, behavior, cell culture, biochemistry and neuroanatomy to tease apart the molecular and cellular contributors to pathological pain sensation. A few of the current projects in the lab focus on defining the roles of specific subpopulations of neuronal and non-neuronal cells to pain sensation, defining the role of RNA binding proteins in the development and maintenance of neuropathic pain, and understanding how rare skin diseases known as palmoplantar keratodermas lead to severe pain in the hands and feet.

The Michael Edidin Lab studies membrane dynamics and organization in cells from lymphocytes to epithelial cells using biochemistry, biophysics (especially fluorescence methods), cell biology, biochemistry and immunology. We are interested in transplantation immunology, particularly in the cell biology of class I MHC molecules, and are working to understand the relationship between plasma membrane biophysics and antigen presentation by MHC molecules. We are currently studying the clustering of T cell receptors for the antigen TCR.