General introduction Ion channels G-protein coupled receptors Second messengers Tyrosine kinase receptors From plasma membrane to the nucleus: Regulation of gene expression Cytokine signaling Cell cycle Apoptosis
Images removed due to copyright considerations. See the following: Figure 1 and Table 1 in Reed SI. 2003. Ratchets and clocks: The cell cycle nover ubiquitylation and protein turnover. Nat Rev. Mol. Cell Biol. 4: 855-864. Figure 1 in Bartek J, Lukas J. Mammalian G1-and S-phase checkpoints in response to DNA damage. Curr Opin Cell
he relationship between structure and function reaches its ultimate expression in the chemistry of amino acids, peptides, and protein Amino acids are carboxylic acids that contain an amine function. Under cer- tain conditions the amine group of one molecule and the carboxyl group of a second can react, uniting the two amino acids by an amide bond. Amide(peptide)bond
The surplus amino acids in animals can be completely oxidized or converted to other storable fuels Amino acids in excess (from diet, protein turnover) can neither be stored, nor excreted, but oxidized to release energy or converted to fatty acids or glucose. Animals also utilize amino acid for energy generation during starvation or in diabetes mellitus
Chapter Amino Acids, Peptides, and Proteins 0. General Introduction Proteins are polymers(多聚体) of amino acids. -20 amino acids(氨基酸)→ millions of proteins with different properties and activities. Protein structures are studied at primary, secondary, tertiary and quaternary levels. -a helix, B sheets, globular, complexes, denaturation and folding. Proteins have widely diverse forms and functions
1. Early studies on the peptide(protein) structure 1.1 The peptide(o=c-n-h) bond was found to be shorter than the C-N bond in a simple amine and atoms attached are coplanar. 1.1.1 This was revealed by X-ray diffraction studies of amino acids and of simple dipeptides and tripeptides
Chapter 5 Macromolecules and Molecular Genetics The key informational macromolecules in prokaryotic and eukaryotic cells are DNA, RNA, and protein. Molecular Genetics deals with the mechanisms by which the information in DNA is replicated, and by which it can be transcribed into rNa and translated into specific proteins
