Biology Exam 3 Notes Review .docx - 1 Biology Genetics 3304 Unit 3 Study Guide 2 Chapter 13 Transcription So Abigail this is what is covered 13.1 RNA

Biology Exam 3 Notes Review .docx - 1 Biology Genetics 3304...

This preview shows page 1 - 11 out of 64 pages.

1 Biology Genetics 3304 Unit 3 Study Guide
Image of page 1

Subscribe to view the full document.

2 Chapter 13: Transcription So Abigail this is what is covered 13.1 RNA Structure and Classes 13.2 Transcription 13.3 Bacterial Transcription 13.4 Eukaryotic Transcription 1. A brief Introduction to RNA 2. Comparisons of DNA and RNA Comparisons of DNA & RNA TABLE 13.1 The structures of DNA and RNA compared Characteristic DNA RNA Composed of nucleotides Yes Yes Type of sugar Deoxyribose Ribose Presence of 2'–OH group No Yes Bases A, G, C, T A, G, C, U Nucleotides joined by phosphodiester bonds Yes Yes Double of single stranded Usually double Usually single Secondary structure Double helix Many types Stability Stable Easily degraded 3. Locations and Functions of different classes of RNA molecules
Image of page 2
3 4. With the exception of some viruses, all RNA is transcribed from a DNA template
Image of page 3

Subscribe to view the full document.

4 5. Transcription a. Synthesis of RNA from a DNA template i. Small section of DNA strands separated ii. RNA synthesized that is complementary to a template DNA strand iii. Template DNA Strand: complementary and antiparallel to RNA iv. Non-template DNA Strand: sequence same as RNA 6. Gene Structure a. Promoter: DNA sequence immediately upstream of transcription start site b. RNA-Coding region: serves as template for RNA synthesis c. Terminator: DNA sequence that causes transcription to stop
Image of page 4
5
Image of page 5

Subscribe to view the full document.

6 How Bacteria Get It Done 1. Bacterial RNA Polymerase a. Synthesized RNA using DNA template b. Core Enzyme: i. Form of the enzyme that synthesizes RNA c. Holoenzyme: Form of the enzyme that initially binds to promoter i. Core enzyme + 2. Transcription Initiation
Image of page 6
7 3. Consensus sequences in Bacterial Promoters 4. Transcription Initiation
Image of page 7

Subscribe to view the full document.

8 5. Transcription Elongation a. Core Enzyme continues to move downstream along gene synthesizing RNA in a 5’ to 3’ direction, adding 1 nucleotide at a time to 3’ end of RNA i. Transcription Bubble DNA strands (-18bp) transiently separated to expose template strand 1. Includes the short DNA sequence base paired with 3’ end of RNA ii. Transcription Pausing Certain DNA Sequences or RNA secondary structures cause RNA polymerase to pause b. Incorporation of incorrect nucleotides can also cause RNA polymerase to pause, back up a short distance, cut off the last few nucleotides form RNA and then continue transcription 6. Gene Structure a. Promoter: Sequence immediately upstream of transcription start site b. RNA coding region: serves as template for RNA synthesis c. Terminator: DNA sequence that causes transcription to stop
Image of page 8
9 7. Transcription Termination a. RHO Dependent i. RNA polymerase synthesizes an RNA that included a Rho utilization (Rut) site that Rho proteins bind to ii. RNA polymerase pauses at a downstream sequence iii. Rho moves 5’ to 3’ along RNA iv. When RHO catches up with RNA polymerase, its helicase activity unwinds RNA-DNA hybrid and releases RNA 8. Transcription Termination a. Rho-Independent i. Terminator region: Inverted repeats followed by > 6 A-T bp’s ii. RNA transcribed from inverted repeats forms hairpin iii. Hairpin in RNA cause RNA polymerase to pause iv. Weakness of U-A bp’s causes RNA to separate from DNA template
Image of page 9

Subscribe to view the full document.

10 9. Rho-Independent Terminator Sequence How Eukaryotes Get It Done
Image of page 10
Image of page 11
  • Spring '14

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask 0 bonus questions You can ask 0 questions (0 expire soon) You can ask 0 questions (will expire )
Answers in as fast as 15 minutes