AIDs class notes

AIDs class notes - genome sum of genetic information in a...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
39/3/07 genome – sum of genetic information in a cell A-T, G-C – only zips if all of the bases are complementary DNA helps make more proteins, which help make more cells Make more DNA- replication, make mRNA copy – transcription (functional non- coding molecules) Complementarity! Protein called DNA polymerase reassembles complementary strand after DNA unzipped (replication) Primer uses Complementarity to fish through genome Melting apart – denaturation Info for making protein is outside the nucleus, so mRNA are like making a photocopy of the DNA in order to translate Like a recipe file: pull out what you need, then put it back (RNA polymerase) How mRNA differs from DNA Ribo, not deoxyribo Substitutes U (uracil) for T (thymine) Single stranded Translation- convert info from RNA to functioning proteins Linear info on mRNA, desire a linear progression of amino acids Complementarity allows tRNA (transfer RNA) to bind to complement on mRNA tRNA has amino acid attached to the top, amino acids float off all in a row three bases is minimum to be able to have coding for 20 amino acids codon – three bases that signify one amino acid AUG- methionine ACA – threonine DNA polymerase has an editing function, but not perfect Mutation change in DNA sequence leads to change in RNA sequence can lead to change in amino acid sequence can lead to change in protein shape or function Polymerase in HIV is sloppiest editor ever found, so it mutates faster than other viruses Human cancers can be caused by one base change (ACA to AAA) Potential effects on protein: no effect, destroy function, create new function, alter shape Shape is key to protein function Sickle cell anemia- globulin forms crystalline spikes, clogs or ruptures blood vessels Antibody (AB)- structure of four proteins Epitope- region of antigen that antibody recognizes
Background image of page 1

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

View Full DocumentRight Arrow Icon
So each antibody can recognize three epitopes Mutations in HIV make it hard for antibodies to recognize it Antibodies cannot build up fast enough, epitope targets no longer remain when full immune response is ready One HIV protein, HIV protease, has a known physical structure Allowed scientists to develop a protease inhibitor, which plugs central cavity where active site of protease is HIV cannot replicate without protease HIV is a retrovirus- goes from RNA to DNA (reverse direction) 9/19/07 Induced immunity Recognition of non-self Auto-immune disease recognizes self as non-self Reaction to non-self Remember non-self Accomplished by three types of white blood cells o Macrophages Antigen presenting cells (APC) o T cells o B cells 1) humoral response- directly attacks things loose in the blood 2) cell-mediated response- destroys infected cells and cancer cells macrophage- processes the antigen, then presents antigen T (helper) cells (T h )- talk to b cells (humoral) and cell mediated (T killer)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/07/2008 for the course BIO 46 taught by Professor Broverman during the Fall '07 term at Duke.

Page1 / 9

AIDs class notes - genome sum of genetic information in a...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online