Nucleicacids(核酸)概述.pptx

Chapter 2 Nucleic Acids核酸;Section 1 The Classification and Chemical Component of Nucleic Acid Section 2 Structure and Function of DNA Section 3 Structure and Function of RNA Section 4 The Physical and Chemical Characters of Nucleic Acid;Nucleic acids are: molecules that store information for cellular growth and reproduction. large molecules consisting of long chains of monomers called nucleotides (核苷酸).;;Classification and distribution of nucleic acids;Formation of a Nucleotide;Pentose Sugars;Nitrogen Bases;Nucleotides with Purines;Nucleotides with Pyrimidines;Names of Nucleosides and Nucleotides;Nucleotides derivatives;Multiple phosphate nucleotides;Multiple phosphate nucleotides;3’,5’-cAMP, 3’,5’-cGMP, used in signal transduction;Coenzymes;;;Primary structure ;;Wilkins Franklin (1952) X-ray crystallography;ds DNA on the English 2 Pound Coin;Secondary structure of DNA;The Watson-Crick Structures;Polymorphisms of DNA:DNA can From Three Types of Helices;SCAU-PQ Mu;B-Z Junctions – an AT pair flipped inside out.;Large DNA molecules are compacted in a cell by supercoiling.;Twisting in the same sense (clockwise）;Supercoil of Eukaryotic DNA;SCAU-PQ Mu;Section 3 Structure of RNA;;SCAU-PQ Mu;Unique features of RNAs;SCAU-PQ Mu;SCAU-PQ Mu;SCAU-PQ Mu;SCAU-PQ Mu;mRNA structure;;5’-cap;5’-cap addition;Roles of cap sequence;Poly A tail;Poly A tailing ;Transfer RNA (tRNA); ;The secondary structure is similar to a cloverleaf (三叶草) . There are four loops (DHU loop, anticodon loop, TψC loop and extra loop), and four stems. ;Reversed L-shape structure;SCAU-PQ Mu;Secondary structure of 18S rRNA ;Three rRNA 52 proteins;SCAU-PQ Mu;Small RNA and RNAomics ;SCAU-PQ Mu;SCAU-PQ Mu;SCAU-PQ Mu;Section 4 The Physical and Chemical Characters of Nucleic Acid;General properties;UV absorption ;Quantify DNAs or RNAs OD260=1.0 equals to 50μg/ml dsDNA 40μg/ml ssDNA (or RNA） 20μg/ml oligonucleotide Determine the purity of nucleic acid samples pure DN