Question

A cell line isolated from a patient shows decreased transcription of the pS2 gene in response to oestrogen.

1) Explain how you would investigate whether all of the key components for the initiation of transcription are recruited to the pS2 promoter in the right order. Include all of the different classes of proteins that you would look for. [15 points]

Answer 1

pS2 gene, whose transcription is stimulated by estrogen in the human breast cancer cell line, MCF-7. The pS2 gene product is a small, secreted polypeptide currently of unknown function, but with structural features similar to some growth factors. The expression of the pS2 gene has so far been detected only in MCF-7 cells and some breast cancer biopsies.

We use mutational studies with oestrogen or without oestrogen.

Without oestrogen pS2 genes would not be transcribed even if they are in the correct order and with oestrogen pS2 gene should be transcribed if the all key components for the initiation are in the right order.

we can mutate one by one component of the factor and study the results by expression of pS2 gene.