Transcriptomics. Flashcards
Define a conctamer?
A strand of cDNA that is formed when multiple cDNA fragments are linked together.
Define a microarray?
A technique that is used to look at gene expression.
Define a macroarray?
A larger version of a microarray.
Define a snapshot?
When a scientific procedure gives results that are only relevant for a specific time.
E.g. Transcriptomics.
Define SNP chips?
Commonly used to detect point mutations.
Define a tiling array?
A technique that is used to look at gene expression across a genome or chromosome.
What is transcriptomics?
The process of analysing all of the mRNA within a cell at a given time.
How does transcriptomics analyse DNA?
It analyses the percentage of the genetic code that is transcribed into mRNA.
Why is transcriptomics context dependent?
As the amount of mRNA within a cell depends on when that cell is analysed.
Why is genomics not context dependent?
Because the number of genes in the organism never changes.
What 4 things does the transcription of DNA into mRNA depend on?
Environment.
Development.
Time of day.
Particular tissue that is being analysed.
What is the major difference between transcriptomics and genomics?
Transcriptomics gives scientists an idea about how genes are expressed within a certain cell or tissue.
Genomics gives an analysis of gene expression throughout the entire body.
What does the study of transcriptomics allow us to compare?
To make compare gene expression in different tissues e.g;
What are 4 comparisons that we can make via the use of transcriptomics?
Different tissues within the same organism e.g. liver cell Vs brain cell.
Same tissues within the same organism e.g. tumour cell Vs non tumour cell.
Same tissues within different organisms e.g. wild type cells Vs mutant cells.
How gene expression changes in certain tissues during development.
What biomolecules will genomics and transcriptomics both study?
The structure and chemical composition of the nucleic acids.
What 3 analytic processes will genomics and transcriptomics use to ananlyse nucleic acids?
Electrophoresis.
Hybridisation.
Sequencing.
What is the biggest challenge of studying RNA strands?
mRNA is very fragile.
How do scientists make mRNA less fragile?
They will use reverse transcriptase to convert coding mRNA back to DNA.
What is one of the major benefits of transcriptomics when referring to mRNA?
It can be used to identify particular classes of mRNA and determine their abundance within the cell.
What are 4 of the major benefits of transcriptomics when referring to specific genes?
It suggests which genes are involved in which biological processes.
It allows scientists to group genes with similar functions together.
It tells scientists which genes are expressed under particular environmental conditions.
It can help to identify genetic markers for disease and to identify changes within the proteome.
What molecular technique is usually used in conjunction with the hybridisation of mRNA?
Northern blot.
What needs to be present for hybridisation processes involving mRNA?
An oligonucleotide containing a sequence of nucleotides identical to a sequence of nucleotides on the cDNA.
What is cDNA formed from?
From the protein coding regions (exons) of mRNA.
How is cDNA made from mRNA?
Via reverse transcription.