Skip to main content
Indiana University Bloomington

Faculty from several departments participate in our Graduate Program. They are listed according to the following research area.

students in labs

Craig PikaardCraig Pikaard

Craig Pikaard
HHMI-GBMF Investigator, Distinguished Professor and
Carlos O. Miller Professor,
Molecular and Cellular Biochemistry Department

Office: Myers Hall 300

Phone: 812/855-1874

Send Email

Lab Website


Ph.D., Purdue University, 1985


Mechanisms of ribosomal RNA gene dosage control via selective gene silencing; enzymes and RNAs responsible forĀ  RNA-mediated DNA methylation; structures, functions and interactions of gene silencing enzymes PolĀ  IV (DNA-Dependent RNA Polymerase IV), Pol V; and RDR2 (RNA-Dependent RNA Polymerase 2); identification and functions of noncoding RNAs directing chromatin modification and gene silencing.

Representative Publications

Chandrasekhara C, Mohannath G, Blevins T, Pontvianne F, Pikaard CS (2016). Chromosome-specific NOR inactivation explains selective rRNA gene silencing and dosage control in Arabidopsis.
Genes and Development. 30:177-90.

Chinmayi Chandrasekhara, Gireesha Mohannath, Todd Blevins, Frederic Pontvianne and Craig S. Pikaard (2015). Chromosome-specific NOR inactivation explains selective rRNA gene silencing and dosage control in Arabidopsis. Genes & Development (in press)

Todd Blevins, Ram Podicheti, Vibhor Mishra, Jing Wang, Doug Rusch, Haixu Tang and Craig S. Pikaard (2015). Identification of Pol IV and RDR2-dependent precursors of 24 nt siRNAs guiding de novo DNA methylation in Arabidopsis. eLife 2015, Oct 2;4. pii: e09591. doi: 10.7554/eLife.09591.

Todd Blevins, Frederic Pontvianne, Ross Cocklin, Ram Podicheti, Chinmayi Chandrasekhara, Satwica Yerneni, Chris Braun, Brandon Lee, Doug Rusch, Keithanne Mockaitis, Haixu Tang and Craig S. Pikaard (2014). A two-step process for epigenetic inheritance in Arabidopsis. Molecular Cell 54:30-42.

Frederic Pontvianne, Todd Blevins, Chinmayi Chandrasekhara, Iva Mozgova, Christiane Hassel, Olga M.F. Pontes, Sarah Tucker, Petr Mokros, Veronika Muchova, Jiri Fajkus, and Craig S. Pikaard (2013). Subnuclear partitioning of rRNA genes between the nucleolus and nucleoplasm reflects alternative epiallelic states. Genes and Development 27:1545-1550.

Jeremy R. Haag, Thomas S. Ream, Michelle Marasco, Carrie D. Nicora, Angela D. Norbeck, Ljiljana Pasa-Tolic and Craig S. Pikaard (2012). In vitro transcription activities of Pol IV, Pol V and RDR2 reveal coupling of Pol IV and RDR2 for dsRNA synthesis in plant RNA silencing. Molecular Cell 48:811-818.

Wierzbicki, A.T., Ross Cocklin, Anoop Mayampurath, Ryan Lister, M. Jordan Rowley, Brian D. Gregory, Joseph R. Ecker, Haixu Tang and Craig S. Pikaard (2012). Spatial and functional relationships among Pol V-associated loci, Pol IV-dependent siRNAs and cytosine methylation in the Arabidopsis epigenome. Genes & Development 26:1825-1836.

Frederic Pontvianne, Chinmayi Chandrasekhara, Wei Feng, Todd Blevins, Hume Stroud, Steve E. Jacobsen, Scott D. Michaels and Craig S. Pikaard (2012).  Histone methyltransferases regulating rRNA gene dose and dosage control in Arabidopsis. Genes & Development 26:945-957

Thomas S. Ream, Jeremy R. Haag, Andrzej Wierzbicki, Carrie D. Nicora, Angela Norbeck, Jian-Kang Zhu, Gretchen Hagen, Thomas J. Guilfoyle, Ljiljana Pasa-Tolic and Craig S. Pikaard (2009). Subunit compositions of the RNA silencing enzymes, Pol IV and Pol V reveal their origins as specialized forms of RNA Polymerase II. Molecular Cell 33, 192-203.

Andrzej Wierzbicki, Thomas Ream, Jeremy Haag and Craig S. Pikaard (2009). RNA Polymerase V transcription guides ARGONAUTE4 to chromatin. Nature Genetics 41: 630-634.

Wierzbicki, Andrzej, Jeremy Haag and Craig S. Pikaard (2008). Noncoding transcription by RNA Polymerase Pol IVb/Pol V mediates transcriptional silencing of overlapping and adjacent genes. Cell 135:635-648.

Pontes, Olga, Carey Fei Li, Pedro Costa Nunes, Jeremy Haag, Thomas Ream, Alexa Vitins, Steven E. Jacobsen and Craig S. Pikaard (2006). The Arabidopsis chromatin-modifying nuclear siRNA pathway involves a nucleolar RNA processing center. Cell 126: 79-92.

Onodera, Yasuyuki, Jeremy Haag, Thomas Ream, Pedro Costa Nunes, Olga Pontes and Craig S. Pikaard (2005). Plant Nuclear RNA polymerase IV mediates siRNA and DNA methylation-dependent heterochromatin formation. Cell 120:613-622