Cell Biology HELP!

[cdmOMR]

---

Members do not see this ad.

I have a test tomorrow and while I was going through a practice problem I encounted a problem. The section that covers this problem was lectured on by a TA and he wasnt very clear on this part. The problem says:

What distinguishing features of serine, threonine, and tyrosine make them the amino acids of choice for kinases?

I know its the alcohol group, but not 100% sure why. Im thinking that it facilitates phosphorylation, but not really sure on that.

What determines whether a particular serine/threonin/tyrosine is modified by a particular kinase?

Im pretty sure this is the particular motif of amino acid side chains surrounding the particular serine/threonine/tyrosine allows the kinase to "target" the serine and others for phosphorylation. But what Im confused on was I thought that the with serine/threonine and tyrosine receptor kinases were unique in that the tyrosine residues (for example) phosphorylate eachother when the receptors dimerize (autophosphorylation). If this is true (which it is) then what role does the kinase play in phosphorylation?

^^^^ my main question

 

[pmantz]

I have a test tomorrow and while I was going through a practice problem I encounted a problem. The section that covers this problem was lectured on by a TA and he wasnt very clear on this part. The problem says:

What distinguishing features of serine, threonine, and tyrosine make them the amino acids of choice for kinases?

I know its the alcohol group, but not 100% sure why. Im thinking that it facilitates phosphorylation, but not really sure on that.

What determines whether a particular serine/threonin/tyrosine is modified by a particular kinase?

Im pretty sure this is the particular motif of amino acid side chains surrounding the particular serine/threonine/tyrosine allows the kinase to "target" the serine and others for phosphorylation. But what Im confused on was I thought that the with serine/threonine and tyrosine receptor kinases were unique in that the tyrosine residues (for example) phosphorylate eachother when the receptors dimerize (autophosphorylation). If this is true (which it is) then what role does the kinase play in phosphorylation?

^^^^ my main question

I think the when the receptors dimerize and phosphoylate each other, they are activating each other so they can in turn phosphorylate a Kinase, which in turn can activate other protiens. I took cell over a year ago so don't quote me.. I remember I thought the G-protien/second messenger system was pretty easy but the tyrosine kinase receptors confused me a little.. For your first question I don't think it has been worked out which serine/tyrosines are phosphorylated yet.

I think the G-protien/second messenger cell signaling is the most documented and is more of a "classic question." ****That are just my opinions though*****

Good Luck, I hope your enjoying your cell course I thought it was one of the more fun/interesting courses I have taken...

 

[cdmOMR]

I think the when the receptors dimerize and phosphoylate each other, they are activating each other so they can in turn phosphorylate a Kinase, which in turn can activate other protiens. I took cell over a year ago so don't quote me.. I remember I thought the G-protien/second messenger system was pretty easy but the tyrosine kinase receptors confused me a little.. For your first question I don't think it has been worked out which serine/tyrosines are phosphorylated yet.

I think the G-protien/second messenger cell signaling is the most documented and is more of a "classic question." ****That are just my opinions though*****

Good Luck, I hope your enjoying your cell course I thought it was one of the more fun/interesting courses I have taken...

Thanks! The G-protien/second messenger process is pretty stright forward. Im just a little hazy on the relationship between the tyrosine kinase and the tyrosine residues because that TA didnt really go over it.

So far I really enjoy it. My teacher is really good at explaining things, although I heard his tests are hard, we'll see. But yea Im kinda looking forward to this class...not so much my Heroes and Epics class though . Thanks again.

Chris