BIOL
BIOL 2050 Lecture 12 Control of gene expression

BIOL 2050 Lecture 12 Control of gene expression - Control...

Info icon This preview shows pages 1–6. Sign up to view the full content.

10/31/2011 1 Control of gene expression BIOL2050 Lecture 12 Control of gene expression in prokaryotes and eukaryotes Prokaryote operons and controlling their transcription The lac operon Methods of controlling gene expression in eukaryotes Overview Explain why gene expression needs to be controlled Outline the four methods of controlling transcriptions in operons Describe how the lac operon functions Describe methods of gene regulation in eukaryotes By the end of this lecture you should be able to...
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

10/31/2011 2 Central dogma of Molecular Biology Molecular basis of connection between genotype and phenotype Does not explain regulation of this flow of information Are all genes needed all the time?? Basic cellular function ‘Housekeeping genes’ Amino acid synthesis Repair DNA Sugar breakdown Response to environment Prokaryotes Are all genes needed all the time?? Basic cellular function ‘Housekeeping genes’ Amino acid synthesis Repair DNA Sugar breakdown Response to environment Prokaryotes ‘Housekeeping genes’ produce RNA and DNA polymerase etc.
Image of page 2
10/31/2011 3 Are all genes needed all the time?? Eukaryotes Are all genes needed all the time?? Eukaryotes Prokaryotes Only a subset of genes that code for proteins are expressed at any one time All cells carry all information Only a subset of genes expressed in each cell type Gene regulation All cells carry all information. Only a subset of this information is expressed. Unicellular flexibility Multicellular specialisation Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

10/31/2011 4 Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation Alter gene structure -Changes in Chromatin Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation Limit production of proteins Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation 5’ cap 3’ tail
Image of page 4
10/31/2011 5 Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation Amount of protein produced depends on rate of mRNA degradation Levels of gene regulation DNA modification Transcription mRNA processing RNA stability Translation and post translation Active or inactive proteins Many bacterial genes with similar functions clustered These are transcribed together Called an operon Genes within an operon are associated together e.g. all catalyse same biochemical reaction.
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

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