Work in the Green Lab is centered on the ribosome. The overall fidelity of protein synthesis appears to be limited by the action of the ribosome, which is the two-subunit macromolecular machine responsible for decoding and translating messenger RNAs (mRNAs) into protein in all organisms. Our work is divided into four general project areas. The longest-standing research area concerns the interactions of eubacterial ribosomes and release factors. The goal is to understand the mechanism of action of release factors on the ribosome. A second research area involves biochemical and structure/function studies of the miRNA pathway, particularly the mechanism of action of the Argonaute proteins and their interacting factors. A third area of work in the lab is centered around regulation of eukaryotic translation, specifically in understanding the mechanism behind various mRNA quality control pathways and the interactions of proteins therein, as well as with the ribosome. The newest area of research in the lab extends our strengths in ribosome biochemistry to characterize the translation status of the cell using the ribosome profiling. We are using this technique to better understand the role of several factors involved in eukaryotic and prokaryotic translation fidelity.

The Gregg Semenza Lab studies the molecular mechanisms of oxygen homeostasis. We have cloned and characterized hypoxia-inducible factor 1 (HIF-1), a basic helix-loop-helix transcription factor. Current research investigates the role of HIF-1 in the pathophysiology of cancer, cerebral and myocardial ischemia, and chronic lung disease, which are the most common causes of mortality in the U.S.

The Goley Lab is broadly interested in understanding cellular organization and dynamic reorganization, with particular focus on the roles of the cytoskeleton in these phenomena. We use cell biological, biochemical, genetic and structural approaches to dissect cytoskeletal processes with the aim of understanding how they work in molecular detail. Currently, we are focused on investigating the mechanisms underlying cytokinesis in bacteria. A deep understanding of cytoskeletal function in bacteria will aid in the identification of targets for novel antibiotic therapies and in efforts in synthetic biology.

The GI Biomarkers Laboratory studies gastrointestinal cancer and pre-cancer biogenesis and biomarkers. The lab is led by Dr. Stephen Meltzer, who is known for his research in the molecular pathobiology of gastrointestinal malignancy and premalignancy. Research in the lab has led to several groundbreaking genomic, epigenomic and bioinformatic studies of esophageal and colonic neoplasms, shifting the gastrointestinal research paradaigm toward genome-wide approaches.

Research in the Chloe Thio lab focuses on several areas. First, HBV virology and immunology in HBV monoinfected and HIV-HBV co-infected individuals that will ultimately help develop a cure for HBV. Second, HCV infection in men who have sex with men. Third, non-alcoholic fatty liver disease with a focus on HIV-infected individuals. Fourth, host genetic determinants of spontaneous HBV recovery and HCV clearance.

Dr. Colantuoni and his colleagues explore human brain development and molecular mechanisms that give rise to risk for complex brain disease. His team uses genomic technologies to examine human brain tissue as well as stem models and vast public data resources.

The Erika Matunis Laboratory studies the stem cells that sustain spermatogenesis in the fruit fly Drosophila melanogaster to understand how signals from neighboring cells control stem cell renewal or differentiation. In the fruit fly testes, germ line stem cells attach to a cluster of non-dividing somatic cells called the hub. When a germ line stem cell divides, its daughter is pushed away from the hub and differentiates into a gonialblast. The germ line stem cells receive a signal from the hub that allows it to remain a stem cell, while the daughter displaced away from the hub loses the signal and differentiates. We have found key regulatory signals involved in this process. We use genetic and genomic approaches to identify more genes that define the germ line stem cells' fate. We are also investigating how spermatogonia reverse differentiation to become germ line stem cells again.

The Bigos Lab focuses on a Precision Medicine approach to the treatment of psychiatric illness. In addition, this lab employs functional neuroimaging and genetics as biomarkers in neuropsychiatric drug development. A recent study used functional MRI to test the neural effects of a drug with the potential to treat cognitive dysfunction in schizophrenia. Other studies aim to identify patient-specific variables including sex, race, and genetics that impact drug clearance and clinical response to better select and dose antipsychotics and antidepressants.

The Berger Lab's research is focused on understanding how multi-subunit assemblies use ATP for overcoming topological challenges within the chromosome and controlling the flow of genetic information. A long-term goal is to develop mechanistic models that explain in atomic level detail how macromolecular machines transduce chemical energy into force and motion, and to determine how cells exploit and control these complexes and their activities for initiating DNA replication, shaping chromosome superstructure and executing myriad other essential nucleic-acid transactions. Our principal approaches include a blend of structural (X-ray crystallography, single-particle EM, SAXS) and solution biochemical methods to define the architecture, function, evolution and regulation of biological complexes. We also have extensive interests in mechanistic enzymology and the study of small-molecule inhibitors of therapeutic potential, the development of chemical approaches to trapping weak protein/protein and protein/nucleic acid interactions, and in using microfluidics and single-molecule approaches for biochemical investigations of protein dynamics.

The Bert Vogelstein Laboratory seeks to develop new approaches to the prevention or treatment of cancers through a better understanding of the genes and pathways underlying their pathogenesis. Our major focus is on cancers of the colon and rectum. We have shown that each colon neoplasm arises from a clonal expansion of one transformed cell. This expansion gives rise to a small benign colon tumor (called a polyp or adenoma). This clonal expansion and subsequent growth of the tumors appears to be caused by mutations in oncogenes and tumor suppressor genes, and the whole process is accelerated by defects in genes required for maintaining genetic instability. Mutations in four or five such genes are required for a malignant tumor to form, while fewer mutations suffice for benign tumorigenesis. As the mutations accumulate, the tumors become progressively more dangerous. Current studies are aimed at the further characterization of the mechanisms through which these genes act, the identification of other genes that play a role in this tumor type, and the application of this knowledge to patient management.