INTRODUCTION TO GENETICS<br />
Genetics is the study of heredity, the process in which a parent passes certain gene onto their children. A person's appea...
History<br /><ul><li>1946 – DNA is the main constituent of genes (Avery)
1950 – First X-ray pictures of DNA (Franklin)
1953 – DNA structure revealed (Watson and Crick)
1970 onwards - Multiple conformations and structures, initially from fibers
1973 - X-ray structure confirms double helix (Rich)
1974 - t-RNA structure (Kim)
1980 – Structure of first complete turn of B DNA (Dickerson)</li></li></ul><li>Location of DNA<br />
In Prokaryotes:- DNA is not separated from the rest of cellular components.<br />In eukaryotes :- DNA is located in the nu...
DNA is bound to proteins forming a complex called chromatin.<br />Less than 0.1% of the total DNA in a cell is present in ...
Chromosome<br />In eukaryotic cells, a linear structure composed of a single DNA molecule complexes with protein. <br />23...
Chromosome Number in Various Organisms<br />Organism<br />Total Chromosome Number<br />Human <br />Chimpanzee<br />Dog<br ...
Histones<br />Electron micrograph of nucleosomes <br />Attached by strands of nucleic acid. <br />
Solenoid<br />
H3-H4 tetramer<br />H2A dimer<br />H2B dimer<br />
DNA Strands<br />
Watson and Crick’s double-helical model of DNA<br />The DNA molecule consists of two polynucleotide chains wound around ea...
2. The two chains are antiparallel. <br />3. The sugar-phosphare backbones are on the outsides of the double helix, with b...
Determination of structure of DNA<br /><ul><li> DNA is composed of nucleotides.
 Nucleotides is composed of a base, a sugar and phosphate.</li></ul> BASE<br />5<br />Base<br />O<br />CH2<br />O<br />C<b...
 Guanine (G)
 Cytosine (C)
 Thymine (T)</li></ul>O<br />O<br />H<br />OH<br />C<br />C<br />O<br />C<br />C<br />1<br />1<br />4<br />4<br />Uracil (...
CHO<br />CHO<br />CHO<br />OH<br />C<br />H<br />OH<br />H<br />C<br />H<br />C<br />H<br />Reduction<br />OH<br />H<br />...
Alpha and Beta Anomers<br />CHO<br />OH<br />H<br />C<br />OH<br />C<br />H<br />OH<br />C<br />H<br />OH<br />C<br />H<br...
The Glycosidic Bond<br /><ul><li>Connects ribose sugar to the base</li></ul>O-glycosides: when hydroxyl group on anomeric ...
N-glycosides<br />N-glycosides: when hydroxyl group on anomeric carbon of a sugar reacts<br /> with an amine N-glycoside i...
  Base<br />5<br />O<br />CH2<br />O<br />C<br />C<br />1<br />4<br />H<br />H<br />  Phosphate<br />H<br />2<br />3<br />...
Each nucleotide consists of a heterocyclic nitrogenous base, </li></ul>   a pentose sugar and phosphate. <br />-<br />O<br...
Nucleoside<br />-<br />-<br />-<br />O<br />O<br />O<br />Nucleoside monosphosphate (NMP)<br />5<br />-<br />Base<br />O<b...
 BASE            NUCLEOTIDE<br />Adenine (A)<br />Guanine (G)<br />Cytosine (C)<br />Thymine (T)<br /> Uracil (U)<br />Ade...
Adenine<br />Cytosine (C)<br />NH2<br />NH2<br />C<br />C<br />6<br />6<br />N<br />N<br />N<br />1<br />1<br />7<br />C<b...
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Biochem introduction to genetics(june.15.2010)

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Biochem introduction to genetics(june.15.2010)

  1. 1. INTRODUCTION TO GENETICS<br />
  2. 2. Genetics is the study of heredity, the process in which a parent passes certain gene onto their children. A person's appearance – <br />height, hair color, skin color, and eye color -- are determined by genes.<br />Gene: a gene is a nucleotide sequence in DNA that specifies a polynucleotide or RNA. <br />
  3. 3. History<br /><ul><li>1946 – DNA is the main constituent of genes (Avery)
  4. 4. 1950 – First X-ray pictures of DNA (Franklin)
  5. 5. 1953 – DNA structure revealed (Watson and Crick)
  6. 6. 1970 onwards - Multiple conformations and structures, initially from fibers
  7. 7. 1973 - X-ray structure confirms double helix (Rich)
  8. 8. 1974 - t-RNA structure (Kim)
  9. 9. 1980 – Structure of first complete turn of B DNA (Dickerson)</li></li></ul><li>Location of DNA<br />
  10. 10. In Prokaryotes:- DNA is not separated from the rest of cellular components.<br />In eukaryotes :- DNA is located in the nucleus , and separated from the rest of the<br />cell by nuclear envelope. <br />
  11. 11. DNA is bound to proteins forming a complex called chromatin.<br />Less than 0.1% of the total DNA in a cell is present in mitochondria. <br />Euchromatin= diffuse chromatin<br />Heterochromatin= dense chromatin<br />
  12. 12. Chromosome<br />In eukaryotic cells, a linear structure composed of a single DNA molecule complexes with protein. <br />23 pairs of chromosomes<br />P= petit (small) <br />
  13. 13. Chromosome Number in Various Organisms<br />Organism<br />Total Chromosome Number<br />Human <br />Chimpanzee<br />Dog<br />Cat<br />Mouse<br />Mosquito<br />Potato<br />Tomato <br />46<br />48<br />78<br />72<br />40<br />6<br />48<br />24<br />
  14. 14. Histones<br />Electron micrograph of nucleosomes <br />Attached by strands of nucleic acid. <br />
  15. 15. Solenoid<br />
  16. 16. H3-H4 tetramer<br />H2A dimer<br />H2B dimer<br />
  17. 17. DNA Strands<br />
  18. 18. Watson and Crick’s double-helical model of DNA<br />The DNA molecule consists of two polynucleotide chains wound around each other<br /> in a right-handed double helix<br />
  19. 19. 2. The two chains are antiparallel. <br />3. The sugar-phosphare backbones are on the outsides of the double helix, with base <br /> orientated toward the central axis. <br />4. The bases in each of the two polynucleotide chains are bonded together by hydrogen<br /> bonds. The specific pairings observed are A bonded with T (2 hydrogen bonds) and <br /> G bonded with C ( 3 hydrogen bonds) and its according to Chargaff’s rule. <br /> They are called complementary base pairs. <br />5.The base pairs are 0.34 nm apart in the DNA helix. A complete turn (360˚) turn of the <br /> helix takes 3.4 nm, therefore there are 10 base pairs per turn. <br />6. <br />
  20. 20. Determination of structure of DNA<br /><ul><li> DNA is composed of nucleotides.
  21. 21. Nucleotides is composed of a base, a sugar and phosphate.</li></ul> BASE<br />5<br />Base<br />O<br />CH2<br />O<br />C<br />C<br />1<br />4<br />H<br />H<br />-<br />H<br />O<br />Purine<br />Pyrimidine<br />2<br />3<br />C<br />C<br />5<br />5<br />P<br />O<br />O<br />O<br />CH2<br />CH2<br /><ul><li>Adenine (A)
  22. 22. Guanine (G)
  23. 23. Cytosine (C)
  24. 24. Thymine (T)</li></ul>O<br />O<br />H<br />OH<br />C<br />C<br />O<br />C<br />C<br />1<br />1<br />4<br />4<br />Uracil (U) instead of Thymine in RNA.<br />H<br />H<br />H<br />H<br />H<br />H<br />SUGAR<br />2<br />2<br />3<br />3<br />C<br />C<br />C<br />C<br /> O H<br />OH<br /> H<br />OH<br />Deoxyribose<br /> (DNA)<br />Ribose<br /> (RNA)<br />
  25. 25. CHO<br />CHO<br />CHO<br />OH<br />C<br />H<br />OH<br />H<br />C<br />H<br />C<br />H<br />Reduction<br />OH<br />H<br />C<br />OH<br />OH<br />H<br />H<br />C<br />C<br />OH<br />H<br />C<br />OH<br />OH<br />H<br />H<br />C<br />C<br />CH2OH<br />CH2OH<br />CH2OH<br />D-Ribose<br />2-deoxy-D-Ribose<br />D-Ribose<br />
  26. 26. Alpha and Beta Anomers<br />CHO<br />OH<br />H<br />C<br />OH<br />C<br />H<br />OH<br />C<br />H<br />OH<br />C<br />H<br />OH<br />C<br />H<br />Hemiacetal linkage formation<br />Hemiacetal linkage formation<br />C<br />H<br />OH<br />C<br />OH<br />H<br />C<br />OH<br />H<br />OH<br />H<br />C<br />O<br />O<br />OH<br />H<br />C<br />OH<br />H<br />C<br />OH<br />H<br />C<br />H<br />C<br />H<br />C<br />CH2OH<br />CH2OH<br />CH2OH<br />D-Glucose<br />Beta- D-Glucose<br />Alpha-D-Glucose<br />Differ in configuration of –OH group on anomeric carbon atom.<br />
  27. 27. The Glycosidic Bond<br /><ul><li>Connects ribose sugar to the base</li></ul>O-glycosides: when hydroxyl group on anomeric carbon of a sugar reacts<br /> with an alcohol (sugar) O-glycoside is formed. <br />O-glycosidic linkage is present in disaccharides and polysaccharides. <br />So, disaccharides, oligosaccharides and polysaccharides are O-glycosides.<br />
  28. 28. N-glycosides<br />N-glycosides: when hydroxyl group on anomeric carbon of a sugar reacts<br /> with an amine N-glycoside is formed. <br />N-glycosidic linkage is present in nucleotides, RNA and DNA. <br />So, nucleotides, RNA and DNA are examples of N-glycosides.<br />
  29. 29. Base<br />5<br />O<br />CH2<br />O<br />C<br />C<br />1<br />4<br />H<br />H<br /> Phosphate<br />H<br />2<br />3<br />C<br />C<br />OH<br />OH<br /> Sugar<br />Nucleotides<br /><ul><li> Monomeric units of nucleic acids.
  30. 30. Each nucleotide consists of a heterocyclic nitrogenous base, </li></ul> a pentose sugar and phosphate. <br />-<br />O<br />P<br />O<br />O<br />
  31. 31. Nucleoside<br />-<br />-<br />-<br />O<br />O<br />O<br />Nucleoside monosphosphate (NMP)<br />5<br />-<br />Base<br />O<br />O<br />P<br />O<br />P<br />P<br />O<br />CH2<br />O<br />Nucleoside diphosphosphate (NDP)<br />Nucleotides<br />C<br />O<br />O<br />O<br />C<br />1<br />4<br />Nucleoside triphosphosphate (NTP)<br />H<br />H<br />H<br />2<br />3<br />C<br />C<br />OH<br />OH<br />
  32. 32. BASE NUCLEOTIDE<br />Adenine (A)<br />Guanine (G)<br />Cytosine (C)<br />Thymine (T)<br /> Uracil (U)<br />Adenosine <br />Guanosine <br />Cytidine <br />Thymidine <br /> Uridine<br />
  33. 33. Adenine<br />Cytosine (C)<br />NH2<br />NH2<br />C<br />C<br />6<br />6<br />N<br />N<br />N<br />1<br />1<br />7<br />C<br />CH<br />5<br />5<br />2<br />2<br />C<br />C<br />H<br />4<br />CH<br />4<br />8<br />CH<br />C<br />3<br />3<br />9<br />O<br />N<br />N<br />N<br />H<br />H<br />Thymine (T)<br />Guanine<br />O<br /> O<br />C<br />C<br />6<br />HN<br />6<br />N<br />1<br />N<br />1<br />7<br />C-CH3<br />C<br />5<br />5<br />2<br />2<br />C<br />C<br />H<br />4<br />8<br />4<br />CH<br />CH<br />3<br />C<br />3<br />9<br />O<br />N<br />N<br />H<br />N<br />H<br />
  34. 34. Base pairing<br />• • •<br />U<br />• • •<br />A<br />T<br />A<br />• • •<br />• • •<br />G<br />C<br />G<br />C<br />• • •<br />• • •<br />C<br />G<br />C<br />G<br />• • •<br />• • •<br />A<br />U<br />A<br />T<br />• • •<br />• • •<br />A<br />U<br />A<br />T<br />• • •<br />• • •<br />U<br />A<br />T<br />A<br />• • •<br />• • •<br />G<br />C<br />G<br />C<br />• • •<br />• • •<br />U<br />A<br />T<br />A<br />• • •<br />• • •<br />G<br />C<br />G<br />C<br />• • •<br />• • •<br />C<br />G<br />C<br />G<br />• • •<br />• • •<br />U<br />A<br />T<br />A<br />
  35. 35. Hydrogen bonds<br />
  36. 36. Thymine<br />H<br />H<br />Adenine<br />H<br />H<br />H<br />C<br />O<br />N<br />N<br />H<br />C<br />H<br />7<br />C<br />C<br />5<br />4<br />H<br />C<br />6<br />C<br />8<br />5<br />C<br />6<br />N<br />3<br />9<br />1<br />N<br />1<br />C<br />4<br />2<br />N<br />N<br />2<br />C<br />3<br />C<br />N<br />H<br />
  37. 37. Cytosine<br />N<br />Guanine<br />H<br />H<br />H<br />O<br />N<br />C<br />H<br />C<br />C<br />H<br />C<br />C<br />C<br />N<br />H<br />N<br />C<br />N<br />N<br />C<br />C<br />N<br />O<br />H<br />N<br />H<br />
  38. 38. 5‘ end<br />3‘ end<br />5‘ end<br />3‘ end<br />
  39. 39. 5’ end<br />O<br />O<br />O<br />O<br />CH2<br />CH2<br />CH2<br />CH2<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />P<br />P<br />P<br />P<br />-<br />-<br />-<br />-<br />O<br />O<br />O<br />O<br />Phosphate backbone<br />Phosphodiester bonds<br />Phosphodiester bonds<br />O<br />3’ end<br />
  40. 40. 3’ end<br />3<br />5<br />5<br />3<br />3<br />5<br />5’ end<br />DNA Strands Are Antiparallel <br />5’ end<br />3’-carbon of the sugar is above 5’-carbon:<br /> The strand is said to run in 3’to 5’ direction.<br />5<br />O<br />O<br />O<br />O<br />CH2<br />CH2<br />CH2<br />CH2<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />P<br />P<br />P<br />P<br />3<br />-<br />-<br />-<br />-<br />O<br />O<br />O<br />O<br />-<br />-<br />-<br />-<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />O<br />CH2<br />CH2<br />CH2<br />CH2<br />O<br />O<br />O<br />O<br />P<br />P<br />P<br />P<br />O<br />O<br />O<br />O<br />5’-carbon of the sugar is above 3’-carbon:<br /> The strand is said to run in 5’to 3’ direction.<br />3’ end<br />The two strands run in opposite direction.<br />
  41. 41. Angstrom Unit= 0.1 nanometer<br />
  42. 42. Types of DNA <br />Predominates in vivo<br />Predominates in DNA-RNA <br />hydrinds<br />The A form, which predominates in DNA-RNA hybrids, is similar to the B form , but is more compact.<br />In the Z form, the bases of the two DNA strands are positioned toward the periphery of a left-handed helix.<br />It is designated “Z” because, in each strand , a line connection the phosphates “zigs” and “zags”.<br />
  43. 43. 有難う御座います<br />

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