Project description:Human APOBEC3 enzymes are a family of single-stranded (ss)DNA and RNA cytidine deaminases that act as part of the intrinsic immunity against viruses and retroelements. APOBEC3s deaminate cytosine to form uracil which can functionally inactivate or cause degradation of viral or retroelement genomes. In addition, APOBEC3 proteins have deamination independent anti-viral activity and aberrant regulation of APOBEC3 expression can result in the deamination and mutagenesis of the genome contributing to cancer initiation and evolution. To further understand their cellular roles, we used affinity purification mass spectrometry (AP-MS) to determine the protein-protein interaction (PPI) network for the human APOBEC3 enzymes and uncovered a diverse number of protein-protein and protein-RNA mediated interactions. PPIs with the Prefoldin family of protein folding chaperones were identified for APOBEC3B, APOBEC3D, and APOBEC3F. The APOBEC3B and prefoldin 5 (PFD5) interaction disrupted the ability of PFD5 to induce degradation of the oncogene cMyc, implicating a deamination independent contribution of APOBEC3B to cancer. Altogether, the results uncover novel functions and interactions of the APOBEC3 family and suggest that they may have fundamental roles in cellular RNA biology, their roles are not redundant, and there is a deamination independent influence on cancer.
Project description:Soft corals are unique amongst animals in their prolific production of bioactive terpenoid natural products that rival the chemical diversity of plants and microbes. We recently established that octocorals uniformly express terpene cyclases and that their encoding genes often reside within putative biosynthetic gene clusters, a feature uncommon in animal genomes. In this work, we report the discovery and characterization of a widespread gene cluster family for the biosynthesis of briarane diterpenoids that number over 600 molecules distinct to corals. We sequenced five genomes from evolutionarily discrete families of briarane-producing octocorals, including the chromosomally resolved precious coral Corallium rubrum, and identified a common five-gene cluster composed of a terpene cyclase, three cytochrome P450s, and a short-chain dehydrogenase. Using Escherichia coli and Saccharomyces cerevisiae as hosts and homologous briarane biosynthesis genes from seven corals, we reconstituted the biosynthesis of cembrene B g-lactone, which contains the g-lactone structural feature distinctive of briarane diterpenoids. The discovery of the genomic basis of briarane biosynthesis not only allows for its biological examination across coral species but establishes that animals, like microbes and plants, also employ gene cluster families to produce specialized metabolites.
Project description:This pilot clinical trial studies different types of energy balance interventions to see how well they work in increasing the physical activity levels of breast cancer gene-positive patients, Lynch syndrome-positive patients, chronic lymphocytic leukemia (CLL) survivors or family members of cancer survivors who are at high risk for cancer. Increasing exercise and eating healthy foods may help reduce the risk of cancer. Studying how well different types of interventions work in motivating cancer survivors or high-risk family members to increase exercise and healthy food choices may help doctors plan the most effective motivational program for cancer prevention.
