The Johri Lab is interested in how evolutionary processes like changes in population size, recombination rate, direct and indirect effects of selection and factors such as genome architecture shape patterns of genomic variation. Work in the lab involves employing computational and theoretical approaches or statistical method development or using an empirical approach to perform evolutionary inference and ask fundamental questions in population genetics. Here are some questions that we are interested in:

Publications

The Gordon Lab at UNC studies interactions between the germ cells and somatic support cells of C. elegans. We want to learn how the germ stem cells influence their stem cell niche and vice versa, and how these interactions change over developmental and evolutionary time.

Macrophages are highly dynamic and widespread blood cells that play many important functions in vertebrates. They are the main phagocytes throughout the body, responsible for clearing away dying cells, damaged tissue, and pathogens, to maintain tissue integrity. Macrophages circulate in the bloodstream as monocytes or are stationed in strategic locations of the body as tissue macrophages where their phagocytic roles are critical, such as microglia in the brain, Kupffer cells in the liver, Langerhans cells in the skin, and osteoclasts in the bone.

Of particular interest are the normal roles and mechanisms of macrophages and microglia in the development and maintenance of the nervous system that remain far less understood than their functions in disease and injury. In the healthy brain, microglia have been implicated in shaping brain circuitry and neuronal development as well as in possibly affecting behavioral outcomes. They have unique embryonic origins from primitive macrophages that migrate into the brain and remain thereafter through life. These versatile glial cells provide the first line of defense and respond to a wide variety of environmental factors, such as protein aggregates, apoptotic cells, injured tissue, and pathogens, as well as to intracellular dysfunctions. Overall, the developmental process by which macrophages take residence and differentiate into tissue macrophages, and the contribution of macrophages to normal animal development remain not well understood.  We are addressing these two fundamental areas of macrophage biology in the context of how macrophages participate in the nervous system.

Research in the lab focuses on how a single genome gives rise to a variety of cell types and body parts during development. We use Drosophila as a model organism to investigate (1) how transcription factors access DNA to regulate complex patterns of gene expression, and (2) how post-translational modification of histones contributes to maintenance of gene expression programs over time. We combine genomic approaches (e.g. chromatin immunoprecipitation followed by high-throughput sequencing) with Drosophila genetics and transgenesis to address both of these questions. Defects in cell fate specification and maintenance of cell identity often occur in human diseases, including cancer. (website)

Curriculum vitae

Our lab group is interested in the behavior, sensory biology, neuroethology, and conservation of marine animals. Topics of particular interest include: (1) the navigation of long-distance ocean migrants such as sea turtles, salmon, spiny lobsters, and elephant seals; (2) magnetic field perception, magnetic maps, and use of the Earth’s magnetic field in animal navigation; (3) natal homing and the geomagnetic imprinting hypothesis in sea turtles and salmon; (4) applications of sensory ecology and movement ecology to conservation biology; (5) neurobiology, behavior, and physiology of marine invertebrates; (6) marine ecosystems and animal health in the Galapagos Islands.  Techniques used range from electron microscopy, immunohistochemistry, and electrophysiology to behavioral studies, oceanographic modeling, and field studies in the ocean. Whenever possible, we favor innovative approaches that cut across traditional academic boundaries and combine elements from disparate fields.