Biotechnology - Microarray
Upcoming SlideShare
Loading in...5

Biotechnology - Microarray






Total Views
Views on SlideShare
Embed Views



0 Embeds 0

No embeds



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

Biotechnology - Microarray Biotechnology - Microarray Presentation Transcript

  • Genomic librarycDNA libraryMicroarrayBiotechnology
  • Genomic LibraryA collection of genesA complete set of recombinant plasmids cloneseach carrying copies of particular segment of thegenome (comprehensive)
  • Shotgun ApproachUses restriction enzyme to randomly cut upgenomic DNA and place it in plasmidsThis process of generating a genomic library cancut up genes because restriction enzymes do notrespect gene boundariesAnimation:
  • cDNA LibrarycDNA = complementary DNAReverse transcribed from mRNAAnimation: Making a cDNAQ: Why can’t eukaryotic DNA be cloned directlyinto prokaryotic cells?
  • Refer to Fig 20.5
  • Slide can hold up to 100 000 pieces of known DNA. The sequence and position of each DNA is known. Information is kept in a database. DNA sequence can be cDNA (genes) oroligonucleotides (i.e. in GeneChip technology)
  • Manufacturing a microarrayAnimation: printing a microarray by robot
  • MicroarrayBenefit: can examine thousands of mRNA (cDNA)strands at the same timeUsed to compare a test sample (treated) to thecontrol (wild type, normal, untreated)
  • Animation: Microarray (1:31) (DNAmicroarray hybridization close up, no sound, 0:55) to “Genes and Medicine”  “Genetic Profiling” “Technique”  “Microarray” animation “Patrick Brown” on the development of the microarray
  • Animation: GeneChip Technology (includesmaking a gene chip array) to “Genes and Medicine”  “Genetic Profiling”“Technique”  “GeneChips” for click-throughanimation“Stephen Fodor” on the development of GeneChiptechnology
  • MicroarrayProcedure1. Extract mRNA2. Reverse transcribe intocDNA incorporatingfluorescent probes green is control /normal / wild typesample red is test sample3. Hybridize to microarray4. Laser scannerquantitates data
  • Scanned Microarray
  • Microarray Green: mRNA producedin control sample (wildtype, normal, untreated) Red: mRNA produced intest sample (treated) Yellow: both samplesproduce the sameamount of mRNA
  • MicroarrayWhich colour dots arethe ones that willinterest theresearcher? Why?Hint: Relate colours togene expression
  • Gene Expression Green: signifies downregulation of a gene intesting conditions Red: signifies upregulation of a gene intesting conditions Yellow: no changes ingene expression whentesting conditions arechanged
  • Activity: MicroarrayThe BackgroundmRNA was isolated from seedlings exposed to lightand darkness during germination. The mRNA willbe reverse transcribed into cDNA and hybridizedonto complementary nucleotides on a microarray todetermine the different genes that are expressed inthe two conditions.