[RASMB] UltraScan AccessGrid Seminar on Thursday

[Borries Demeler]

Dear Colleagues,

Our next monthly UltraScan AccessGrid seminar will take place on Thursday,
April 8th, from 11 am - 12:00 pm Central Time in the UTHSCSA UltraScan
AccessGrid venue (England time: 5 pm, Central Europe: 6 pm).

This month Dr. Nikola Wenta, University of Nottingham, will report
on physiological implications of the conformational rearrangement of
STAT1 dimers

The Abstract of his talk is: 

The activation/inactivation cycle of STAT transcription factors entails
their transition between different dimer conformations. Unphosphorylated
STATs can dimerize in an antiparallel conformation via their N-domains,
whereas STAT phosphorylation triggers a parallel dimer conformation with
mutual phosphortyrosine:SH2 domain interactions, resulting in DNA-binding
and nuclear retention. Our results obtained by AUC, SEC and EMSAs
demonstrated that both dimer conformations were present simultaneously
and of equal stability (Kd ~40 nM), irrespective of the phosphorylation
status. However, tyrosine phosphorylation enforced the formation
of parallel dimers, thus shifting the abundance of the dimerization
interfaces. Our research now focuses on the physiological implications
linked to the transition between both dimer conformations. According
to the current model, the antiparallel conformation is required
not only for receptor binding and STAT phosphorylation, but is also
essential for the dephosphorylation of STAT1. Crystal structures of
the antiparallel dimer and our own results revealed that reciprocal
interactions between Coiled-Coil and DNA binding domain (DBD), in
addition to N-domain interactions, contribute to the stabilization of
the antiparallel conformation. It is established that the interaction of
the DBD with importin is required for nuclear import of phosphorylated
STAT1. We used AUC-SE and SEC to investigate the stoichiometry of this
interaction. Furthermore, our experiments demonstrated an inhibitory
role of importin binding in STAT1 dephosphorylation. On the other hand,
arrestin was shown to facilitate STAT1 dephosphorylation by an so far
unknown mechanism. Thus, our research will include the characterization
of arrestin interactions with STAT1 as well.


If this is your first time connecting to the UltraScan AccessGrid seminar
I strongly recommend that you test out your connection with Jeremy Mann
(jeremy at biochem.uthscsa.edu) 1-2 days prior to the meeting.

See you Thursday, -Borries

P.S. apologies if you received multiple copies of this message since it was
posted to multiple mailing lists.

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PLEASE NOTE:

The UltraScan seminar is broadcast over the AccessGrid. In order to
participate you will need to have AccessGrid 3.0.2 or higher installed
on your computer. If you are not on a multicast network (most likely
you will not have this capability), you need to connect via unicast,
and you will need to use a unicast/multicast bridge to communicate
(Tools:Bridges in the Venueclient menu). You can use the following
MC-bridges to connect to our venueserver: Argonne, NCSA and the UTHSCSA
bridge. Participants are strongly encouraged to test their connections
one or two days in advance with Jeremy Mann (jeremy at biochem.uthscsa.edu)

Additional information and links to free AccessGrid software can be
found at:

http://www.accessgrid.uthscsa.edu

Instructions for installing it on Windows or Linux is available at:

http://accessgrid.uthscsa.edu/wiki/doku.php

The seminar will take place in the UltraScan room in the 3.1 venue server
of the University of Texas Health Science Center at San Antonio. The
venue address for the UTHSCSA Lobby is:

https://ag1.v19.uthscsa.edu:9000/Venues/default (AccessGrid 3.x)

There will be a 1 hour testing time - 10-11 am central time.  Please
contact Jeremy Mann at jeremy at biochem.uthscsa.edu or 210-567-2672 for
assistance. I recommend to test out your AccessGrid connection one or
two days in advance of the meeting if you have never set it up before.