19 Sep '13 14:31>2 edits
How does mature mRNA travel from where it is produced in the cell nucleus to the nuclear pore? Is it by simple diffusion? Or does it hitch a ride on a molecular motor on a microtubule? Or what?
Also, once a signaling molecule that regulates a particular gene get inside the cell nucleus via entry through a nuclear pore, how does it travel to exactly the right particular gene to turn it on or off despite there being thousands of genes? I mean, how can it tell when it has found the right gene and how does it find its way to that exactly right location when it would surely be like looking for a needle in a vast haystack? does it get there by simple random diffusion or does it hitch a ride on a molecular motor on a microtubule or what? Or does it somehow turn the gene on or off by some other means that is indirect and doesn't involve physically getting directly at the gene itself?
I repeatedly tried to Google all this but got absolutely nowhere.
Also, once a signaling molecule that regulates a particular gene get inside the cell nucleus via entry through a nuclear pore, how does it travel to exactly the right particular gene to turn it on or off despite there being thousands of genes? I mean, how can it tell when it has found the right gene and how does it find its way to that exactly right location when it would surely be like looking for a needle in a vast haystack? does it get there by simple random diffusion or does it hitch a ride on a molecular motor on a microtubule or what? Or does it somehow turn the gene on or off by some other means that is indirect and doesn't involve physically getting directly at the gene itself?
I repeatedly tried to Google all this but got absolutely nowhere.