Question

Assignment 1. - Word File Insert Design Layout References Mailings Review View Tell me what you want to do Sign in Share Home Cut Find Aria E Copy Paste Select Editing Format Painter Clipboard Paragraph Font 9 leads to cell division when the target gene is transcribed. When the signal is present, will the target gene be Styles (5) The following is a diagram of the RTK signalling pathway. Assume that when the signal is present the pathway Ligand Receptor transcribed? Extracellular Cytoplasm What components of the pathway cause cancer if th they are mutated? List three Adaptor P protein (SOS) Nucleus GNRP Active trans- RAS Inactive transcription cription actor factor RAS GDI For each of the components you listed above, what kind of mutation would be necessary for them to cause cancer? That is, is the mutation dominant, gain of function, or recessive, loss of function? Also, state how the mutation would change the activity of the protein. GTP RAF Modulation of Page 5 of 7 1121 words Ц8 English Canada) 甲 + 130% 3:30 PM O Type here to search ^回 瘟脈 ENG 2018-10-06

Answer 1

1. If the signal is present, the target gene will be transcribed as the cascade of activations will also activate the transcription factor.

2&3. The following components can cause cancer in the RTK pathway on mutation -

• mutation in ras/raf genes leading to loss of tumor suppression (loss of function by inactivation)
• mutation in ERK activation (gain of function), enabling it to phosphorylate Elk-1 and lead to the transcription of proto-oncogene fos on a higher scale than normally seen.
• mutation in the modulation of transcription (gain of function) leading to uncontrolled transcription of the protein.