Guillermo Calero
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Phone (412) 383-5319
Fax (412) 648-9008

University of Pittsburgh
1040 Biomedical Science Tower 3


Guillermo Calero

Associate Professor
Department of Structural Biology

My laboratory at the University of Pittsburgh, works on reconstitution of multi-protein complexes (MPCs) for biochemical and X-ray crystallographic studies. In particular we are interested in MPCs involved in: 1) nuclear events such as transcription initiation and DNA repair, and 2) Interactions of membrane receptors with their cytoplasmic partners. Since MPCs cannot be isolated as a whole from cells, we have developed biochemical tools that have allowed us to express and purify individual components (monomeric or multimeric) to reconstitute such MPCs. Our ultimate goals is to crystallize and perform structural studies using X-ray crystallography of these samples which posses great biological interest. We are also participating in development of methods using EM to identify best diffracting nano-crystals for femtosecond diffraction experiments.

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Education & Training

Baylor College of Medicine
Facultad de Medicina, UNAM
M.D. 1991

Cornell University
Ph.D. 2003 in Chemistry and Chemical Biology

Stanford University
Postdoctoral Scholar 2003-2008

Representative Publications

Murakami K, Calero G, Brown CR, Liu X, Davis RE, Boeger H and Kornberg RD (2013). Formation and fate of a complete, 31-Protein, RNA polymerase II transcription initiaition complex. Journal of Biological Chemistry.

Wehbi VL, Stevenson HP, Feinstein TN, Calero G, Romero, G and Vilardaga JP (2013). Non-canonical GPCR signaling arising from  a PTH-arrestin-GS complex. Proc Natl Acad Sci U S A. 110(4):1530-5.

Stevenson HP, Mahkov AM, Calero M, Mathews I, Lin G, Santamaria H, Ross TM, Soltis M, Koshla S, Conway J, Cohen A and Calero G (2014).  Electron Microscopy Screening   of Protein Nano crystals for Serial Femtosecond Crystallography. Proc Natl Acad Sci U S A. 111(23):8470-5.

Stevenson H.P., DePonte D.P., Makhov A.M., Zeldin O.B., Calero G*, and Cohen A.E* (2014). Transmission electron microscopy as a tool for nano-crystal characterization pre- and post-injector. Philosophical Transations B. Philosophical Transactions B. 17;369:1647 * Corresponding author

Calero G, Cohen A.E, Luft J.R and Snell E (2014). Identifying, studying and making good use of macromolecular crystals. Acta Crystallographica F. 70:993-1008

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Active Grants

Structural Studies of RNA Polymerase II Transcription Initiation and Elongation
01/15/15 – 12/31/19
National Institutes of Health

Structural and Functional Mechanisms of PTH-Receptor Signaling
07/01/14 – 05/31/18
National Institutes of Health