The Molecular, Cellular & Physiological Biology Area is proud of its many lab classes and the connection to biomedical research. Undergraduate and graduate students often work side-by-side and are encouraged to present their research findings at national meetings and to submit manuscripts for publication in peer-reviewed journals.
Lisa Banner - diabetes; neuroregeneration; immunology
The nervous and immune systems consist of complex networks of cells that monitor signals and respond in a specific manner. These systems are intimately connected and communicate bidirectionally. This implies that signals are involved. Cytokines are a group of polypeptides used as signals between cells of the peripheral immune system and the central nervous system. The main question I am interested in is how do cytokines coordinate interactions between the nervous system and the immune system. One approach to address this question of coordination is to analyze the regulation of cytokines when the system is perturbed, for example, in response to stress. Stress can be achieved in a variety of ways. For my studies, adult mice are placed in a novel environment; this is a well-known model for psychological stress. Subsequently, the mice are analyzed for changes in cytokine levels. Additional lines of research include examining the pathways that link stress to the onset of pathogenesis, the roles other factors play in stimulating cytokine release in both the nervous and immune systems and the regulation of cytokines and their receptors throughout development and after injury.
Chhandak Basu - plant cell and molecular biology, biotechnology
We are interested in production of value-added compounds (including biofuel and biodiesel) in plants and algae. Our goal is to produce genetically engineered plant cells and use these cells as factories for production of biofuel and biodiesel.
Randy Cohen - feeding preferences; neurotransmitter control
My laboratory investigates the physiological and biochemical effects that neurotransmitters have on the behavior of animals. (1) We studying the deleterious effects of glutamate excitotoxicity in the central nervous system. Many human disorders are presumably caused by this phenomenon, including ischemia, Huntington's disease, and epilepsy. Using a rat model, showing an abnormal change in glutamate receptors in two brain regions, my laboratory focuses on the cause and effects of dysfunctional receptor systems. Specifically, what glutamate receptors types are involved in this widespread biomedical dysfunction? What roles do various intracellular molecules have in reducing or exacerbating this phenomenon? (2) We are also studying the role of various neuro-transmitters in the regulation of feeding behavior in insects. Specifically, what are the roles of various neurotransmitters? Do they enhance or diminish food intake? Are specific nutrients influenced by concentrations of a particular neurotransmitter?
Maria Elena de Bellard - cellular mechanism of neural crest cell migration
Ph.D. City University of New York
Office: Citrus Hall 3216B
Neural crest cells are a stem cell population that migrates from the neural tube early in development. They migrate extensively throughout the embryo and form most of the head and peripheral nervous system, giving rise to sensory and sympathetic ganglia, heart regions, glia, head bones, teeth, muscle cells, sensory organs, melanocytes and other cell types. My laboratory is studying the cellular mechanisms responsible for coordinating the migration of these cells. This is of relevance to the mechanism by which cancer metastasizes cell fate determination in stem cells.
Jonathan Kelber - developmental genes and cancer
The Developmental Oncogene Laboratory seeks to characterize the molecular mechanisms and normal or oncogenic functions of genes that play important roles during development but also contribute to cancer in the adult. Our work integrates molecular/cellular biology, signaling biochemistry, animal models of normal development and disease, and microscopy to answer questions in this field.
Ernest Kwok - plant cell biology, chloroplast structure
I am studying the relationship between organelle morphology/location and cellular physiology in plant cells. Of primary interest is the structure and function of plastid stromules. Stromules are thin projections of the outer and inner envelope membrane of plastids (including chloroplasts). These structures are highly dynamic, changing shape and length rapidly. Because of their small diameter, stromules are very difficult to observe using conventional bright field microscopy. Stromules are best observed using fluorescent proteins that accumulate in the aqueous interior of plastids: the stroma. Previous work identified proteins that inhabit the interior of stromules and investigated the relationship between stromules and the cytoskeleton. At present, the function of these structures is unknown. However, their ability to increase the surface area/volume ratio of the plastid suggests they may be involved in exchange of metabolites and/or membrane components with the cytosol or other organelles. Currently, my lab is trying to determine the relationship between stromule formation and plastid division and the cell cycle. This work is being conducted in tobacco and Arabidopsis, using suspension cell cultures.
Stan Metzenberg - mathematical biology; protein science
I work on "dry" problems in mathematical and computational biology, as well as "wet" problems in protein science. I am currently building a theory of a non-Darwinian, non-neutral driver of evolution, developed conceptually through differential equations and computer simulations. By computational analyses of large data sets, I am studying the signature of this putative evolutionary driver in the sequence record of extant species. In the "wet" parts of my lab, I engineer recombinant enzymes (e.g. microbial dehydrogenases) for potential use in biosensors. The genes for these enzymes are identified from genome sequence databases, cloned from synthetic codon-optimized sequences and expressed in recombinant prokaryotic or eukaryotic hosts (E. coli, P. pastoris), using a bioreactor. I make targeted changes to the genes by site-directed mutagenesis, which allows me to better understand the relationship between the structure and function of the enzyme, and to try to improve its performance. I am also involved in education, having served a term on the California Curriculum Development and Supplemental Materials Commission and more recently in assisting two Persian Gulf nations in teacher-leader training as their education ministries implement advanced core curricula in biological science for their public schools.
Mary-Pat Stein - intracellular trafficking; Legionnaire's disease
My research focuses on the mechanisms of intracellular trafficking with particular emphasis on the ability of pathogens to alter normal cellular trafficking events to evade clearance by the host. Legionella pneumophila, the causative agent of Legionnaire’s disease, is a gram-negative bacterium that lives in fresh water amoeba and which can also invade human macrophages in the lung. L. pneumophila inhibits normal intracellular transport to lysosomes where the bacteria would be destroyed and then recruits host cell ER-derived vesicles to its vacuolar membrane. Both of these processes are dependent on the expression of a functional type IV secretion apparatus called the Dot/Icm system. This apparatus allows Legionella to inject bacterial effector proteins in the host cell cytosol. Remodeling of the L. pneumophila-containing vacuole creates an intracellular environment permissive for bacterial growth. My laboratory is currently working on identifying the L. pneumophila proteins responsible for the recruitment and fusion of host cell vesicles to the vacuolar membrane.
Maria Elena Zavala - plant cell biology; hormones controlling root development
I use plants as model systems to investigate problems in development and growth. Development proceeds in an orderly sequence and is the result of genes being turned on and off in a coordinated fashion. I am interested in understanding the regulation of gene expression on a cellular and tissue level. My students study how roots growl We have focused our attention on a cluster of cells, the quiescent center, that appear to be directly involved in maintaining normal growth and function. These cells provide progenitor cells for the surrounding meristems. We would like to know if the lines of communication are altered during growth and development and how new lines are maintained. We are also working on the types of signals involved in stimulating the development of new meristems in root tissue. These studies will help us understand how normal root growth is regulated and will allow us to gain an insight into the how cells become specialized and maintain their specialization.