First name,Last name,Preferred title,Overview,Position,Department,Individual
Kathryn,Ryan,Instructional Associate Professor,"1. Delineate the function of the Ran cycle in NPC assembly
Model for NPC AssemblyRan is a small GTPase that cycles between a GTP and GDP bound form to regulate many nuclear processes. All 4 components of the Ran cycle were isolated in the npa screen. Characterization of these mutants revealed membrane defects and the accumulation of nucleoporin containing vesicles in the cytoplasm. The accumulation of such vesicles in these npa mutants suggests that NPC assembly involves a Ran-mediated vesicular fusion event at the outer nuclear envelope. In this model of NPC assembly, a subset of nucleoporins is first concentrated in vesicles (A). When the vesicles fuse with the outer nuclear membrane in a Ran-dependent manner (B), a critical, localized concentration of these nucleoporins triggers pore formation (C) and nucleates new NPC assembly (D and E). To test the model, work is being done to characterize these vesicles. This includes biochemical approaches to purify vesicles and cell biological and genetic approaches to determine how vesicle-associated proteins contribute to NPC assembly. In addition, we are working to understand how Ran interacts with these vesicles to mediate vesicle fusion to the outer nuclear membrane.
2. Define additional steps in the NPC assembly pathway
There are events both upstream and downstream of the Ran cycle in the assembly pathway. Further cloning and characterization of mutants from the npa collection will continue to identify factors involved in other steps of NPC biogenesis and provide a platform from which to study these discrete events.",Instructional Associate Professor,Biology,https://scholars.library.tamu.edu/vivo/display/n613870d1
Michael,Manson,Professor,"Bacteria have a limited behavioral repertoire. Their most conspicuous behavior is chemotaxis - the pursuit of molecules that are favorable to acquire and the avoidance of chemicals that are best to avoid. The simplicity of bacterial motility and chemotaxis and the amenability of the model species Escherichia coli to genetic, biochemical and physiological manipulation have facilitated rapid advances in understanding the molecular mechanisms of biological energy conversion and signal transduction.
Our laboratory studies the inputs and outputs of chemotaxis. Ligands interact with the periplasmic receptor domain of a chemotactic signal transducer that spans the cell membrane. This interaction is converted into an intracellular signal that is communicated to the flagella. Molecules can be sensed either by binding directly to a receptor or by first interacting with a periplasmic binding protein, which then interacts with a receptor.",Professor||Professor,Biology||Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/ne190242a
Wayne,Versaw,Professor,"Compartmentalization of metabolic pathways and other cellular functions is a hallmark of eukaryotic cells. This feature is extreme in plants due to the presence of organelles not found in most other eukaryotes - plastids. Plastids are a diverse group of interrelated organelles that perform a wide range of metabolic functions including photosynthesis, nitrogen and sulfur assimilation and the synthesis of amino acids, starch and fatty acids. These functions are coordinated with metabolic processes in the cytosol through dynamic exchange of metabolites and ions across the plastid inner envelope membrane.
My lab is studying phosphate (Pi) transport processes that link the metabolic pathways in the plastid and cytosol. The concentrations of Pi in the cytosol and plastid stroma influence photosynthesis and the partitioning and storage of fixed carbon. Transporters involved in the movement of Pi across the plastid inner membrane include members of the pPT, PHT2 and PHT4 families. We are using genetics, cell biology, biochemistry and molecular physiology to investigate the function and physiological roles of these transporters. Recent findings suggest that some members of the PHT4 family are targeted to chloroplasts, whereas others function in heterotrophic plastids and one resides in the Golgi apparatus.
Other projects in the lab include the genetic and biochemical characterization of Pi transport processes in the filamentous fungus Neurospora crassa. Mutants with altered phosphate uptake properties have been isolated, and these have led to the identification of Pi transporter genes, as well as genes with putative regulatory functions.",Professor,Biology,https://scholars.library.tamu.edu/vivo/display/nea6b0d01
Paul,Hardin,Distinguished Professor,"A diverse array of organisms including prokaryotic and eukaryotic microbes, plants, and animals display daily rhythms in physiology, metabolism and/or behavior. These rhythms are not passively driven by environmental cycles of light and temperature, but are actively controlled by endogenous circadian clocks that are set by environmental cycles, keep time in the absence of environmental cues, and activate overt physiological, metabolic and behavioral rhythms at the appropriate time of day. This remarkable conservation of circadian clock function through evolution suggests that maintaining synchrony with the environment is of fundamental importance. Our understanding of the circadian clock is particularly important for human health and well-being. The clearest examples of circadian clock dysfunction are those that result in abnormal sleep-wake cycles, but clock disturbances are also associated with other ailments including epilepsy, cerebrovascular disease, depression, and seasonal affective disorder. The realization that disorders of the sleep-wake cycle such as Familial Advanced Sleep Phase Syndrome can result from alterations in clock gene function underscores the clinical importance of understanding the molecular organization of the circadian system.
Work in my laboratory focuses on defining the molecular mechanisms that drive circadian clock function in the fruit fly, Drosophila melanogaster. We previously found that the core timekeeping mechanism is based on core and interlocked transcriptional feedback loops. Our studies currently focus on (1) defining post-translational regulatory mechanisms that operate in the core loop to set the 24 hour period, (2) determining whether interlocked loops are important for circadian timekeeping and/or output, (3) understanding how circadian oscillator cells are determined during development, and (4) defining mechanisms that control rhythms in olfactory and gustatory physiology and behavior.",Distinguished Professor,Biology,https://scholars.library.tamu.edu/vivo/display/nf27056c4
Richard,Gomer,Distinguished Professor,"Our laboratory is working on three areas of biomedicine, trying to move observations from basic research into the clinic. First, we are studying how the sizes of tissues and tumors are regulated, and how this can be manipulated for therapeutic purposes. As a model system, we are using the simple eukaryote Dictyostelium discoideum, which allows us to combine techniques such as biochemistry, genetics, computer modeling, and cell biology to study tissue size regulation. We have found that a secreted protein as well as the unusual molecule polyphosphate are signals in negative feedback loops that inhibit Dictyostelium cell proliferation, and we are studying the signal transduction pathway to understand similar mechanisms in humans.
Second, we are studying how some secreted proteins can make cells move away from the source of the signal. We found such a signal (called a chemorepellent) in Dictyostelium, and then found a similar signal in humans. We are working to understand the signal transduction pathway for both. The human signal repels neutrophils, and we found that this can be used therapeutically in mouse models of neutrophil-driven diseases such as rheumatoid arthritis and acute respiratory distress syndrome.
Third, we have found that a human blood protein called Serum Amyloid P (SAP) regulates a key step in the formation of scar tissue as well as the formation of the scar-like lesions in fibrosing diseases such as congestive heart failure and pulmonary fibrosis. We are studying this mechanism, and a biotech company (Promedior, now sold to Roche) we co-founded is testing SAP as a therapy for fibrosis in patients in a Phase 3 trials.",Distinguished Professor,Biology,https://scholars.library.tamu.edu/vivo/display/nf41f3898
Matthew,Sachs,Professor,"Understanding the mechanisms by which upstream open reading frames (uORFs) in mRNA transcripts control gene expression is currently the major focus of my laboratory. A substantial component of this work is focused on the uORF-encoded fungal arginine attenuator peptide (AAP). The major goal of this work is to understand the mechanism by which a nascent peptide encoded by this uORF controls the movement of ribosomes on mRNA and regulates gene expression. Control mechanisms mediated by uORFs and nascent peptides exist in mammals, fungi, plants, viruses, and bacteria, but relatively little is known of the molecular details of such control. The AAP is encoded by a uORF in the 5?-leader regions of mRNAs specifying the first enzyme in fungal arginine (Arg) biosynthesis. Synthesis of the AAP rapidly reduces gene expression in response to Arg. AAP-mediated regulation is observed in vivo in both Neurospora crassa and Saccharomyces cerevisiae and in vitro, using fungal, plant and animal extracts. The nascent AAP causes the ribosome to stall when the concentration of Arg is high.",Professor,Biology,https://scholars.library.tamu.edu/vivo/display/nfe74574c