First name,Last name,Preferred title,Overview,Position,Department,Individual
Timothy,Devarenne,Associate Professor,"We study the biochemical and molecular mechanisms underlying the control of programmed cell death (PCD) in plants and how PCD is manipulated during plant-pathogen interactions. Specifically we study the interaction between tomato and Pseudomonas syringae pv. tomato (Pst) the causative agent of bacterial spot disease. Resistance to this disease is conferred by the host Pto serine/threonine protein kinase which recognizes Pst strains expressing the type III effector protein AvrPto.
PCD is induced during both resistant and susceptible plant-pathogen interactions. In the case of a resistant interaction, PCD induced by the plant, known as the hypersensitive response (HR), and acts to limit the spread of the pathogen. In susceptible plant-pathogen interactions plant PCD is induced by the pathogen after infection leading to death of the host. Studies have indicated that the genes controlling host PCD during the HR are the same genes that are manipulated by the pathogen during susceptible interactions. The difference lies in the timing of controlling the activity of these genes; HR PCD occurs within 12 hours of pathogen recognition while pathogen-induced PCD occurs several days after infection.
Many of these genes that control plant PCD are serine/threonine (S/T) protein kinase. We are interested in studying a specific class of S/T protein kinases that control PCD in plants called AGC kinases and how they are regulated in both resistant and susceptible plant-pathogen interactions. Additionally, when plants are not attacked by pathogens, PCD is a process that requires constant control so that cell death does not occur. We are looking at the signaling mechanisms and pathways employed to keep PCD under check in non-pathogen challenged plants.",Faculty Affiliate||Associate Professor,Energy Institute||Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/n11411275
Tatyana,Igumenova,,"My laboratory is broadly interested in understanding the structural basis of signal transduction events that occur at the membrane surface. These events are mediated by signaling proteins that reversibly associate with membranes in response to binding second messengers, such as Ca2+ ions, diacylglycerol, and phosphoinositides. One of the key kinases regulating these signal transduction pathways is the Protein Kinase C (PKC) family. Aberrant levels of PKC expression or activity have been implicated in a large number of human diseases, such as cancer, cardiac failure, Alzheimer's disease, and diabetes. Despite the significance of PKC in signal transduction and human health, the structural and dynamical basis of its activation upon binding to lipid membranes remains elusive.",Associate Professor,Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/n1c6e6632
Xiuren,Zhang,Professor,"Our laboratory focuses on systemic analysis of biochemical, molecular and biological functions of AGO family proteins (AGOs-mics) in genetically tractable Arabidopsis and economically important crops (i.e. rice). We'd like to identify the small RNAs, mRNA targets and protein components which associate with these AGOs. We will study protein/RNA and protein/protein interactions in these RISC assembly events. Our goal is to understand how these AGOs are functionally specialized or redundant corresponding to endogenous development cues and external environmental stimuli. Particularly, we'd like to learn how plants reprogram their gene expression through the small RNAs and AGOs to construct a new cellular niche in responses to environmental challenges and biotic stresses.
Another aspect of our research involves host/virus interaction. Plants take advantage of RNA silencing pathways to defend themselves from exogenous nucleic acid invaders (i.e. viruses). As an anti-host defense mechanism, viruses encode suppressors that can block RNA silencing responses. We have recently demonstrated that CMV 2b disables AGO1 cleavage activity to inhibit RNA silencing and to counter host defense. We are now extending our study to suppressors of several other viruses and the molecular mechanisms of their suppression.",Associate Professor,Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/n220933ad
Junjie,Zhang,Associate Professor,"The living cell contains a collection of molecular machines to grow and function. These machines include the ribosomes, the chaperons, the proteasomes and other enzymes. Malfunction of these machines, if occurred in human, are related to many diseases. Understanding their three-dimensional (3D) structures is essential to understand how these machines work in the cell and eventually to treat those related diseases.
Here we use an experimental technique called cryo-electron microscopy (cryo-EM) to image these cellular machines in their native environment at liquid nitrogen temperatures. We then use image processing and graphics techniques to visualize their 3D structures, answering the questions such as how they assemble and how they interact with each other.
In addition, we develop computational modeling tools to interpret and animate these obtained 3D structures to further describe their movements and dynamics.",Associate Professor,Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/n701e163f
Hays,Rye,Associate Professor,"A fundamental principle of biology is the use of chemical energy in the form of ATP to assemble, disassemble and alter macromolecular structure. Specialized control proteins known as molecular chaperones are often responsible for this activity and have been recognized in recent years to be essential for regulating many aspects of cellular biology. Using a variety of biophysical and biochemical techniques, the Rye lab focuses on three fundamental cellular processes that require molecular chaperones: (1) protein folding (2) protein disaggregation and (3) vesicle trafficking. In each of these cases, large quantities ATP are burned, resulting in molecular organization in the case of protein folding, and molecular disassembly and remodeling in the case of protein disaggregation and vesicle trafficking. We are interested in understanding the detailed biophysical mechanisms that underpin these events. Why are these processes so energetically expensive? Are there any similarities in how the energy is used between these very different molecular processes? Are there general principles of energy transduction in biology that can be gleaned by comparing these examples with other molecular machines, such as cytoskeletal motors? Understanding how molecular chaperones control protein and membrane organization will provide key insights into not only basic cell biology, but will also illuminate aspects of many diseases that spring from aberrant protein and membrane dynamics.",Associate Professor,Biochemistry and Biophysics,https://scholars.library.tamu.edu/vivo/display/ne7fb85e1