1 / 26

Nucleic Acids: Structure, Roles, and Genetic Information

This guest lecture covers the fine structure of nucleic acids, their multiple cellular roles, and the importance of gene sequence. Learn how to draw a dinucleotide and list the functional properties of nucleic acids. Understand the properties that make nucleic acids suitable for carrying hereditary information.

abrienda
Download Presentation

Nucleic Acids: Structure, Roles, and Genetic Information

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 2 Nucleic Acids Guest Lecture: Israel Lidsky

  2. Quizzes • What you need to know on quizzes is covered in lecture • You will have one of today’s structures on the quiz

  3. Aims • Nucleic Acids: fine structure • Nucleic Acids: Multiple cellular roles • Genes: sequence matters

  4. Learning Outcomes • Draw a dinucleotide • List functional properties of nucleic acids • List properties of nucleic acids that make them suitable as carriers of hereditary information

  5. Figure 02.09A: A step-wise method for drawing a deoxyribonucleotide. Keywords Ribose Ribonucleic Acid Deoxyribonucleic Acid Phosphate Group Ribose Nitrogenous Base Dehydration Negative Charge Clues How to actually draw it

  6. Figure 02.09B: A step-wise method for drawing a deoxyribonucleotide. Keywords Nitrogenous Base Ring Structure Purines Pyrimidines Adenine Thymine Guanine Cytosine Hydrogen Bonds GC Content

  7. Figure 02.09C: A step-wise method for drawing a deoxyribonucleotide. Keywords dNTP

  8. Figure 02.10: Distinctinctive features of ribonucleotides. Keywords Ribonucleic Acid Uracil Mono- Di- Tri-

  9. Figure 02.11: The general structure of a nucleic acid. Keywords Linear Polymer Elongation 5’ to 3’ Phosphate Backbone Pyrophosphates ~Hint Quiz Hint~

  10. Sample Quiz Question Two ______ are released whenever DNA elongates by addition of a single ______ • Nitrogenous bases : Phosphate Group • Water Molecules : Nucleotide • Phosphate Groups : Nucleotide • SyFy Rip-Offs : Sci-Fi Blockbuster

  11. Figure 02.12A: Level 1 of DNA organization is a double stranded, antiparallel double helix held together by hydrogen bonds between base pairs. Keywords DNA Double Helix Double Stranded Antiparallel 5’ to 3’ Right Hand Rule Hydrogen Bonds Base Pair

  12. Figure 02.12B: A 3D drawing showing the spatial arrangement of the nucleotides in a DNA double helix.

  13. RNA • Single Stranded (except for SiRNA) • Can carry information Messenger RNA (mRNA) • Has Enzymatic, Structural, and Interfering properties • Not limited to simple structures

  14. Transfer RNA • Anticodons which recognize codons • Bound to amino acids • Deliver amino acids to rRNA Yeast Phenylalanine tRNA Graphic submitted to Wikipedia by Yikrazuul

  15. Ribosomal RNA (rRNA) • Two Subunits • Contains proteins • Site of protein synthesis Small Subunit Large Subunit Thermus thermophilus (animated by David S. Goodsell)

  16. Figure 02.05: An overview of translation in eukaryotes. Animated

  17. Central Dogma Transcription Translation DNA RNA Protein Replication

  18. Figure 02.01: Some forms of information storage in cells. DNA has “cellular information” in nucleus RNA has intermediate roles towards protein synthesis in the cytosol Other forms of information are used by the cell

  19. DNA and Genes • DNA carries genetic information (not obvious) • DNA is : • Linear • Polar • Reproducible (minimal error, nucleotides easily recognized) • Transcribes efficiently (dNTPs are small and plentiful) • Language with few letters and small words for all 20 amino acids • Mutable

  20. Figure 02.04: The smallest function unit of DNA is a gene. Keywords DNA Gene Regulatory Sequence Coding Sequence Exon Intron RNA Splicing

  21. Figure 02.03: DNA information is "read" by proteins. Keywords DNA Gene Regulatory Sequence Transcription factors Proteins

  22. Figure 02.02: Mistakes in DNA replication may cause mutations.

  23. Figure 02.06: Mutations can alter amino acid sequence and protein function.

  24. Figure 02.07: A single point mutation causes sickle cell disease. Mutation in code brings change. Affects to survival: good bad benign Survival itself is context dependent

  25. Figure 02.08: Mutations accumulate slowly in a population of cells. Wear Sunscreen

  26. Learning Outcomes • Draw a dinucleotide • List functional properties of nucleic acids Information storage, regulatory control, information transfer & conversion, enzymatic, structural, interference • List properties of nucleic acids that make them suitable as carriers of hereditary information Linear molecule, polarity, quickly transcribed, synthesizing four nucleotides is efficient, simple codons call for all amino acids and starts and stops, and mutable

More Related