Luciano A. Marraffini (Rockefeller)

Luciano A. Marraffini (Rockefeller)

Butler Seminar Series

Event Date/Location

April 7, 2017 - 4:00 pm
Thomas Laboratory 003

Speaker

  • Photo of Dr. Luciano Marraffini

    Luciano A. Marraffini

    Associate Professor
    The Rockefeller University

    Dr. Marraffini received his undergraduate degree from the University of Rosario in Argentina in 1998 and his Ph.D. from the University of Chicago in 2007, studying bacterial pathogenesis in the laboratory of Dr. Olaf Schneewind. He was a postdoc at Northwestern University from 2008 to 2010 with Dr. Erik Sontheimer, where he pioneered studies on CRISPR-Cas immunity. Dr. Marraffini determined that that CRISPR-Cas systems target DNA molecules in a sequence-specific manner, a study that was key to understand the mechanisms of CRISPR immunity at the molecular level. This finding also predicted the existence of RNA-programmable Cas nucleases and their applications. In 2010 he joined Rockefeller University as assistant professor. He is a 2012 Rita Allen Foundation Scholar and a 2011 Searle Scholar and is the recipient of a 2012 NIH Director’s New Innovator Award, a 2015 Burroughs Wellcome Fund PATH Award, the Earl and Thressa Stadtman Scholar Award from the American Society for Biochemistry and Molecular Biology, and the Hans Sigrist Prize from the University of Bern. For more information about Dr. Marraffini please visit http://marraffini.rockefeller.edu.

Topic

CRISPR-Cas, the adaptive immune system of prokaryotes

Clustered, regularly interspaced, short palindromic repeat (CRISPR) loci and their associated (Cas) proteins provide adaptive immunity against viral and plasmid infection in prokaryotes. The CRISPR-Cas immune response can be divided into two phases. Upon infection, short phage or plasmid sequences known as spacers integrate between CRISPR repeats. This is known as the immunization stage. During the second phase, the targeting phase, spacers are transcribed into small RNA guides that identify the viral or plasmid targets of CRISPR immunity. The CRISPR RNA guides are loaded into Cas nucleases and direct them to complementary sequences in the invading genome. Cleavage of the target genome results in the end of the infection. I will discuss recent work in my lab which shows how these two phases of the CRISPR-Cas immune response are fundamentally linked.

Audience

Free and open to the university community and the public.

Host

Bonnie Bassler, Department of Molecular Biology