Microarrays: Theory and Application By Rich Jenkins MS Student of Zoo4670/5670 Year 2004 Genetics in Motion - Prior techniques were sufficient for limited
studies - But completion of genomic studies opened more avenues - A need for the ability to examine how many genes relate to many other genes Enter Microarrays Types of Arrays
Oligonucleotide arrays - Commonly called DNA chips - Affymetrix and others - 5-50 mer oligos per probe - multiple probes per gene - 260,000+ probes per chip - Attachment usually by photolithography, followed by an incubation period
Types of Arrays cDNA arrays - Commonly called DNA microarrays - 500-5000nt per probe - 1 probe per gene - <10,000 probes possible - Attached usually by solution treatment, followed by an incubation period
Attachment Strategies cDNA Synthesis Issues Normal PCR does not decently reflect the initial concentrations of mRNA in the cell. Several rounds of linear amplification based on cDNA synthesis and a template-directed in vitro transcription reaction (cDNA/IVT) are now being used, in a system that does
not produce the same inconsistencies as PCR What goes on chips?
cDNA libraries ESTs Sequence variants homologs Reading the Chips One sample will fluoresce red when hybridized with on
chip probes, the other will fluoresce green. If both hybridize, then the well will fluoresce yellow. Neither sample hybridizing with a given wells probes is indicated by black.
Reading the Chips Affymetrix GeneChip array Oligo Vs. cDNA Oligo Vs. cDNA Part II DNA chip drawbacks:
Possibly provide too much data Require fairly expensive equipment or must be sent to a commercial firm DNA microarray drawbacks:
Do not measure as great a variety of hybridization Often use only one probe to test a given gene Oligo Vs. cDNA Part III DNA chips
Common uses: - Expression profiling - New gene identification - Polymorphism analysis - Large scale sequencing
DNA microarrays Common uses: - Expression profiling - New gene identification - Polymorphism analysis Microarray uses
Transcriptome analysis New gene discovery through function and the guilt-by-association principle Polymorphism analysis Proteomic analysis Toxin effect identification Pharmacological development Guilt by Transcription
cDNA created from library of cells currently active mRNA (partial cellular transcriptome). Genes without known function that express consistently with known genes are often assumed to be similar in function to
the known gene. Databases So you have all this data searching with NCBI Proteomic Analysis Chips are under development to supercede current Western blot procedure for protein
analysis. Current protein information from chips is gleaned mostly from transcriptome analysis. Proteomic Analysis Toxin effects may be measured by their effects on the current levels of mRNA in a cell, compared to the mRNA profile of either a normal, healthy cell and/or a cell
that has a non-sense mutation in the same region as that affected by the toxin. Proteomic Analysis Using a process similar to that of toxin analysis, the pharmacological industry has begun using microarrays to determine the area of protein synthesis affected by a given drug. This type of research may cheapen
and speed drug development greatly, since hit or miss approaches with poorly understood biochemical pathways might be avoided. Conclusions Microarrays will play a very important role in the near future of genetics, and biology as a whole, and may provide the genetic
equivalent of the chemists periodic table. New technologies will continue to rise from the need to process and store the masses of information gathered from microarray analysis. Thank you
Per indirizzare il cambio di polarità ad un solo nucleo la corrente che viene fatta passare da un solo filo sarebbe insufficiente, ma nel punto in cui interseca la corrente dell'altro filo allora ha abbastanza forza per variare il campo...
Create two new boxes and use the same formatting as the previous step. Colour one in yellow and place the second larger one beside it. This can be done quicker by coping and pasting the first box created in step...
It's easy to be misunderstood in an email, IM or text. When you are joking about something, add a smiley face or JK to ensure the recipient knows that you are joking. Be a friend, not a bystander. ... If...
Select one of the three Connection tools (Google Hangout, Skype, or FaceTime) and create an account (or login with Google Apps for Edu). Then, send one person down the hall, and make your call. Plug in challenges are small tasks...
Approaches to numerical differentiation. Numerical differentiation is carried out on data that are specified as a set of discrete points. If there is a need to calculate the numerical derivative of a function that is given in an analytical form,...
Chapter 1 What is Economics? Section 1-1: The Basic Problem in Economics What is economics? The study of how people satisfy their unlimited wants and needs with limited resources (people have to make choices) Wants vs. Needs: Wants are anything...
Plague of Athens (430 BC) Peloponnesian War between Athens and Sparta. Plague lasted 3 years. Killed ~25% of Athens population . Including Pericles . Likely Typhoid fever or a Hemorrhagic Fever like Ebola. Caused a withdraw of the Spartans because...
3 years of science (Achieve, 2014). NGSS . requires a revision of instructional practices. Students pursuing STEM careers will require a pipeline of enrichment courses to support their interest and curiosity in the sciences and engineering. Earth Science is an...
Ready to download the document? Go ahead and hit continue!