Describe the effects of the over-expression of mdm2 on cell proliferation and apoptosis on cell signaling pathways and metabolism or cell cycle control.

Using M cyclin-Cdk as a specific model describe the different ways it can be activated or de-activated.

The LacY gene codes for the production of the lactose transport protein. Which of the following is true of a mutant cell containing only mutant, non-functional LacY protein and growing in high lactose, low glucose conditions? These cells will be unresponsive if glucose concentrations increase. O Lactose concentrations will rise in the cell. Glucose concentrations will rise in the celI. These cells will be unable to utilize lactose as an energy source.

How are tissue-specific transcription factors regulated? Identify three different ways

LysR regulators like llvY repress transcription from their own promoters. This is called a negative feedback loop. Why might negative feedback be a good way to control expression of a transcriptional repressor? This type of negative feedback loop ensures that ilvC transcription will always be repressed when llvY levels are low, and ilvC will be transcribed highly when llvY levels are high. This type of negative feedback regulation ensures that ilvY is never transcribed. Since llvY is a transcriptional repressor, it will slow down cell growth by blocking transcription. So, llvY represses it's own transcription so that no llvY can ever be made, and the cell can grow. This type of negative feedback loop ensures that there is always a moderate amount of llvY. When IlvY levels fall too low, transcription from the promoter will increase since IlvY won't be able to repress it's own promoter. This negative feedback also ensures that IlVY levels don't rise too high - when llvY levels are high,…

Many currently marketed drugs exert their pharmacological effects by binding to ligand-activated transcription factors and modulating gene expression. One example, are various drugs that target the estrogen receptor to treat breast cancer, osteoporosis and post-menopausal symptoms. Below is a ChIP experiment examining the effects of no drug treatment (C), the natural hormone estrogen (E) and the drugs tamoxifen (T) and raloxifene (R) on recruitment of coactivators (SRC-1 and CBP), Histone Deacetylase Complexes (HDACs) and acetylation of histones associated with the C-myc gene. Which of the following statements are correct based on this data (select all that apply)?

Is the regulation shown (denoted by?) positive or negative regulation? Explain why the type of regulation shown here is advantageous for the cell

Describe how the anaphase-promoting complex (APC) is activated in cells (name the cellular/molecular components involved).

List the regulatory mechanisms that might be lost in a cell producing faulty p53.

1. Hyperproliferation or cell cycle arrest; cell cycle arrest or accumulation of dna; hyperproliferation or growth stress  increase or decrease