Raleigh 9600866 Elucidating how the amino acid sequence determines structure, the protein folding problem, is a central issue in modern structural biology. This proposal describes an integrated approach to studying the folding of the protein L9, a multidomain ribosomal protein. This protein forms an interesting bilobal structure with a compact N-terminal domain connected by a long solvent exposed a-helix to a compact C-terminal domain. The N-terminal domain is a stable folding unit and represents one of the simpler examples of an important class of layered sheet-helix structures. This type of structure is found in other ribosomal proteins and in many small RNA binding domains. Relatively little is known about the interactions which stabilize this important structure or how it folds. The L9 protein also offers a excellent model system to study the folding of multi-domain proteins. In recent years, considerable effort has been devoted to elucidating the folding pathways of single domain globular proteins but much less is known about the folding of multidomain proteins. The folding pathway of this protein will be explored using kinetic measurements. The equilibrium and kinetic folding transitions of the isolated domain and of the full L9 protein will be studied. These experiments will indicate if interactions between domains affect the folding or stability of the protein. The unfolded state will be characterized by Nuclear Magnetic Resonance and Circular Dichroism. Studies of peptide fragments will be used to address the role of local interactions in stabilizing the N-terminal domain. These studies will also identify any potential folding initiation sites. Fragment complementation experiments will be used to probe the role of tertiary interactions in stabilizing nascent secondary structure. Taken together, these experiments will provide a detailed description of the folding pathway and of the interactions which stabilize this interesting protein. One of the major challenges of teaching at a lar ge university is balancing undergraduate education with research. Many of the students feel that they are "lost in the shuffle" or that undergraduate education is ranked a distant third behind research and graduate education. On the other hand, the available research infrastructure has the potential to allow undergraduates unique opportunities. The educational aspects of this Career Award include a number of initiatives designed to integrate undergraduate students into the research life of the department. A new course "Current Trends in Biological Chemistry" is being developed. This course is designed to introduce undergraduates to research areas in modern biological chemistry and is built around the departmental seminar series in biological chemistry. An informal seminar series designed to introduce students to the many career options available to chemists and biochemists is also being developed. One of the core undergraduate courses, physical chemistry laboratory is being extensively revised and redefined. New, more relevant experiments have been introduced and more interactive methods of teaching are being used. At the graduate level, a new program in biological chemistry is being designed. This includes a new seminar series, which also forms the basis of the course "Current Trends in Biological Chemistry': the establishment of a new degree option in the Department of Chemistry, the design of a new course on Protein Structure and the writing of an interdepartmental training grant. %%% Elucidating how the amino acid sequence determines structure, the protein folding problem, is a central issue in modern structural biology. This proposal describes an integrated approach to studying the folding of the multidomain ribosomal protein L9. Considerable effort has been devoted to elucidating the folding pathways of single domain globular proteins but much less is known about the folding of multidomain proteins. The isolated domains of this molecule are also of interest. The N-terminal domain is a st able folding unit and represents one of the simpler examples of an important type of structure found in ribosomal proteins and in small RNA binding domains. One of the major challenges of teaching at a large university is balancing undergraduate education with research. Many of the students feel that they are "lost in the shuffle" and that undergraduate education is ranked a distant third behind research and graduate education. The educational aspects of this Career Award include a number of initiatives designed to integrate undergraduate students into the research life of the department. These include the development of new courses and a new undergraduate seminar series. At the graduate level, a new program in biological chemistry is being designed. This includes the establishment of a new degree option in the Department of Chemistry. ***
