B016786 - MOLECULAR BIOLOGY

Italian

Structure and function of nucleic acids. DNA duplication and mechanisms of control of duplication mistakes. DNA damage and mechanisms of repair. Genome structure. Transposons. Chromatin structure. Transcription: mechanisms of control in prokaryotes and eukaryotes. mRNA maturation. Mechanism of translation and genetic code. Protein localization in the cell. RNA interference. Immunoglobulins: structure, function and somatic recombination. Cell cycle regulation. Oncogenes and onco-suppressors.

Biologia molecolare (Capranico et al.) – EdiSESBiologia molecolare del gene (Watson) – ZanichelliBiologia molecolare della cellula (Alberts) - Zanichelli

Acquisition of basic knowledge of Molecular Biology. Understanding the principal mechanisms of molecular interaction and control of the main cell activity.

Contents of the “General Biology” course.

Lectures

Course of the I semester of the II year

Oral exam

RNA and DNA structures. Denaturation and renaturation of the double helix. DNA A, B and Z. DNA interacting proteins. Plasmids and electrophoresis. DNA supercoiling and topoisomerase. DNAses. Restriction and modification enzymes. Generalities on plasmids and cloning experiment. DNA duplication: structure and activity of DNA polymerase (exonuclease and polymerase activity, processivity). Duplication initiation. Pol III and Pol I dependent synthesis. Enzymes present at the replication fork. Telomerase. Mechanisms of correction of duplication mistakes: proof-reading during duplication and post-replicative mechanisms (miss-match repair, MMR). DNA damages (deamination, alchylation, oxidation, thymin dimer formation ecc.) and mechanisms of repair (base excision repear, BER; nucleotide excision repear, NER). Role of mutagens in genetic disorders and in tumors. Ames test.Holloway junction and molecular mechanism of meiotic recombination. Genome structures: C value paradox, number of genes. Gene density, unique and repetitive sequences. Genome evolution. Gene duplication. Ortologe and paralog genes. Globin cluster, homologous and non-homologous recombination. Different type of pseudogenes. Tandem repeat genes (rRNA, tRNA, histons). Highly repeated sequences: satellite DNA. Moderately repeated sequences: transposons and retrotransposons of viral and non-viral type. Structure and life cycle of retroviruses. Chromatin structure: DNA-protein interaction. Chromatin plasticity: histon modification. Topoisomerase and its action on DNA. RNA transcription. Prokaryotic promoter and RNA polymerase: mechanisms of regulation. Eukaryotic transcription and regulation: general and proximal factors. Enhancers. The “mediator complex”. Chromatin remodeling, transcriptional factor structure. Inhibitors. Polyadenylation and termination. Splicing and alternative splicing. Regulatory mutations: beta-thalassemia. Epigenetic regulation. GpC islands and DNA methylation. Imprinting. Histon and chromatin modifications. mRNA nuclear export. The translation process: tRNA, rRNA and AA-tRNA synthetase. Ribosomes. Translation initiation. Translation elongation, termination and regulation. Antibiotics. The genetic code and the “wobbling phenomenon”. Codon number and codon preference. ORF (open reading frames) and point mutations. RNAi (RNA interference): miRNA and siRNA. Secretion and membrane proteins. Mitochondrial and chloroplast proteins and genomes. Immunoglobulin structure and interaction with an antigen. Somatic recombination, generation of the antibody diversity. Humoral immunity response and adaptation. SCID mice. The vaccines. Cell cycle: cycline and CDK. Check points and regulation. Apoptosis: extrinsic and intrinsic pathways. Pro- and anti-apoptotic genes. Proto-oncogenes and oncogenes. Onco-suppressors. Retroviral oncogenes. Examples of mutation-dependent molecular mechanisms that lead to proto-oncogene activation or to onco-suppressor inactivation.