I have been
on a rotation project in the lab of Dr. D. Nathans, who has received the
Nobel
Prize in 1978 for his work on restriction enzymes. Though I have spent
only two month in his lab, I believe it was my richest scientific experience
that had the most profound influence on the development of my scientific
views.
The project
involved in vivo labeling of NIH3T3 cells with P32 and immunoprecipitation
of JunB protein with polyclonal antibodies. I demonstrated that JunB
is phosphorylated on Ser and Thr by doing phosphoaminoacid
analysis. I purified radioactively labeled JunB by SDS PAGE and
cleaved the eluted protein with CnBr.
To find which peptide contained radioactive label I used four antibodies
raised against different parts of JunB protein. The radioactive JunB
peptide found by this approach contained phosphorylation sites similar
to c-Jun protein, which is a JunB homolog.
Since I have
obtained promising results during my first rotation in Jeff Corden’s lab
and because I was interested more in the understanding of the CTD function,
I left Nathan’s lab to continue my work on the C-terminal domain of RNA
polymerase II. Please, read D. Nathans reference
on myself upon my graduation.