Evaluating Data about Genetic Expression (AQA A Level Biology)

Interpret & Evaluate Data about Genetic Expression

RNA analysis

• RNA analysis is important with regards to gene expression

• From the outside, most cells look almost identical with the same DNA in their nucleus however they are most likely expressing different genes

• When a cell expresses a gene, RNA is produced by transcription

• The RNA present in a cell can be analysed and scientists can match the RNA present in a cell to specific genes and work out which genes are being expressed in that specific cell

• RNA analysis can be used to find the function of a cell and to determine the differences between cells in a healthy person and a patient with a specific illness

  • For example, the genes responsible for tumour formation can be detected by analysing which genes have been over-expressed within a cancer cell

  • This can lead to the discovery of drugs that block the expression of these genes

Analysing an unknown pathway

• Gene expression by transcription factors are controlled by signalling pathways

• Within signalling pathways, proteins bind to each other causing conformational changes (changes in the 3D structure of the protein)

  • This activates the protein and enables it to move on to bind to the next protein in the pathway

• ATP can be used to phosphorylate, and therefore activate, a protein in a signalling pathway