tyrosine kinase receptors?

[AndreyE]

I've been reading a lot on the topic, and by now know about GRB2, SoS, MAPK etc etc.... but at the end I'm all confused.... a lot of reading but my most important question never answered

so what's the classification of tyrosine kinase receptors and how cytokine receptor, insulin receptor, jak-stat, receptor-associated tyrosine kinase fall into this classification?

Wiki is also very much confusing on this.
Are those all the same? Or how they differ?
Really, not a single publication on the Internet or textbooks...
The main concept is missing...

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[Phlame217]

Most of what you listed fall into the "Membrane Bound Receptor" class which are enzymes that are bound directly to the membrane.

Take a look at the Rapid Review Biochem if you have it, maybe even first aid and be sure you are clear about the classes of receptors such as the GPCRs, Membrane Bound Receptors, etc...

 

[AndreyE]

I have rapid-review, it's way too much high yield to go beyond family medicine
My guess is that insulin receptor is a kind of tyrosine kinase receptor.
jak-stat receptor is a kind of receptor-associated tyrosine kinase.
cytokine receptor is a kind of jak-stat receptor (and vice versa).

If I'm not wrong about everything that's mentioned above, then may I say that "receptor-associated tyrosine kinase" (that falls in wikipedia into a separate class of receptors without mentioning much about it) and "tyrosine kinase receptor" are actually the same thing since they both recruit intracellular TK???

I'm trying to classify BcR, TcR, cytokines, prolactin, interferon, interleukin among receptors....

 

[Chirurg]

I've been reading a lot on the topic, and by now know about GRB2, SoS, MAPK etc etc.... but at the end I'm all confused.... a lot of reading but my most important question never answered

so what's the classification of tyrosine kinase receptors and how cytokine receptor, insulin receptor, jak-stat, receptor-associated tyrosine kinase fall into this classification?

Wiki is also very much confusing on this.
Are those all the same? Or how they differ?
Really, not a single publication on the Internet or textbooks...
The main concept is missing...

There are two concepts here you are talking about:
1. Tyrosine-Kinase-Receptors
- Mostly Growth Factors and Insulin
2. Tyrosine-Kinase-Associated Receptors
- Mostly for Cytokines, Growth Hormones, Prolactin, BC-R and TC-R is of same type

1: After binding of the ligand (GFactor), this receptor can autophosphorylate its Tyrosine residues --> activation of GRB2 --> activation of SOS-proteins --> Activation of RAS and it's downstream signalling kinases (like Raf-Kinase, MAP-kinase) --> activation of Transcription Factors which translocate into the nucleus


2: After binding of the ligand (Cytokines), this receptor dimerizes --> Tyrosine Kinases (which are called JAKs) are recruited --> these JAKs crossphosphorylate the dimer --> this leads to activation and Dimerization of STAT which translocates into the nucleus and causes Transcription

difference between 1 and 2:
1 can autophosphorylate, it has intrinsic Tyrosine Kinase activity
2 has to recruit JAK, which does the Kinase activity

 

[AndreyE]

Thanks, that explains a lot. Like that it's actually two differnt types of receptors.

This helped in search which concluded that Tyrosine-Kinase Associated Receptors: Receptors that associate with proteins that have tyrosine kinase activity. Which is mostly cytokines.
JAK apparantly is cytokine-1 type of receptors which is for IL-2 receptor, growth hormone and erythropoietin
Also JAK is for cytokine-2 type, which is for interferons
Other types deal with everything else....

And then I look at TK-receptors... they deal with..."typically growth factors, cytokines and hormones".... I'm laughing ^) It's like am I now being stupid or what? ^) Someone needs to do complete re-write for wikipedia and other sources...
Looks like I have to know the whole classification, which is truly insane....

UPDATE: now it's much clear. So much I don't need further reading. I guess problem solved.