There is a tyrosine kinase, p56lck, binds
>to the cytoplasmic portion of the CD4 receptor resulting in tyrosine
>phosphorylation of the TCR zeta chain(s) (?).
>At the same time, the TCR cytoplasmic region binds
>another tyrosine kinase molecule, I think called p59fyn which also results
>in tyrosine phosphorylation. Phospholipase C becomes activated leading to
>hydrolysis of PIP2 into DAG (?), which then activates PKC, and IP3 in
>turns raises the intracellular Ca+. In the end, the transcription of the
>IL2 gene is able to take place.
>>Since this is not so fresh in my mind, I do stand to be corrected. Any
>signal transductionists care to take a shot?
Almost there. Take another look at your textbook- its in there
somewhere! (I could recomend a good one, but that may be seen as
advertising) Or you could read Weiss, Cell 76, 263-74 1994.
