Anyone who has watched a TV crime drama has a basic idea of DNA. Your DNA is your genetic fingerprint; it distinguishes you from your neighbor and links you to your parents. Although true, the CSI description of DNA is only a part of the story. DNA is more like an instruction manual, the longest, largest, most detailed instruction manual EVER.
Each cell in our body acts like a large international company with a couple thousand employees and DNA as the corporate handbook. In every large company there is a subset of employees that are responsible for market research; the 'receptors' of information get an idea of the current environment and reports back through the cellular hierarchy to the corporate center, ie, the nucleus. While information is working it way up the ladder, proteins within the communication route become excited, recruit others and sometime even provide feedback. Finally at the end of the communication network is a transcription factor (TF). TFs are the urgent memo that gets handed directly to the CEO. The TF is special in that it acts as a key to the DNA and only unlocks specific chapters of the manual thus giving the cellular CEO the exact information and instructions to make the necessary changes to the business practices; make the company grow, make more products, expand to a new location, shut down completely.
If you want to get a global picture of what is going on in a company, looking at all the memos that cross a CEO’s desk is a good place to start. Paralleled in the cell, looking at the ‘active’ TFs in the nucleus (how well it can bind to and ‘unlock’ the DNA) gives a good measure of cellular status and of the upstream signaling network. In a company, you can potentially find failures in communication or in the structure of the company by studying the corporate memos; did some information get pass on too quickly? did something important get left out? were duplicate memos received? We can use the same basic ideas to identify markers in disease in a cell. By comparing the TF activity profiles of cancer cells verses healthy cells we can more precisely pinpoint where things went wrong and therefore develop more directed therapy.
Each cell in our body acts like a large international company with a couple thousand employees and DNA as the corporate handbook. In every large company there is a subset of employees that are responsible for market research; the 'receptors' of information get an idea of the current environment and reports back through the cellular hierarchy to the corporate center, ie, the nucleus. While information is working it way up the ladder, proteins within the communication route become excited, recruit others and sometime even provide feedback. Finally at the end of the communication network is a transcription factor (TF). TFs are the urgent memo that gets handed directly to the CEO. The TF is special in that it acts as a key to the DNA and only unlocks specific chapters of the manual thus giving the cellular CEO the exact information and instructions to make the necessary changes to the business practices; make the company grow, make more products, expand to a new location, shut down completely.
If you want to get a global picture of what is going on in a company, looking at all the memos that cross a CEO’s desk is a good place to start. Paralleled in the cell, looking at the ‘active’ TFs in the nucleus (how well it can bind to and ‘unlock’ the DNA) gives a good measure of cellular status and of the upstream signaling network. In a company, you can potentially find failures in communication or in the structure of the company by studying the corporate memos; did some information get pass on too quickly? did something important get left out? were duplicate memos received? We can use the same basic ideas to identify markers in disease in a cell. By comparing the TF activity profiles of cancer cells verses healthy cells we can more precisely pinpoint where things went wrong and therefore develop more directed therapy.
External signals work their way to the nucleus to effect gene regulation. http://en.wikipedia.org/wiki/File:Signal_transduction_pathways.png |