Guarding the Germ-line Stem Cell Genome: Biogenesis and Function of Piwi-Interacting RNAs (piRNAs)
Posted January 11, 2011
Despite relatively frequent mutations to their genome, organisms manage to suppress the high levels of phenotypic variation that would otherwise accompany these mutations. Scientists believe this ability to maintain the germline genome in the face of environmental influence is related to the functioning of a recently discovered class of small non-coding RNA called Piwi-interacting RNA (piRNA). These small regulatory RNA molecules bind to specialized proteins, called "Piwi" proteins, from the Argonaute family, but their biogenesis and mechanisms of action still remain largely a mystery.
At a half-day meeting on November 3rd, 2010 scientists met at the New York Academy of Sciences to discuss the burgeoning body of research on these intriguing molecular actors. In their presentations researchers covered everything from the discovery of piRNAs and Piwi proteins in human fetal oocytes and in neuronal cells of Aplysia to these molecules' role in both genome maintenance and gene expression. Though there is much left to understand about, among other properties, the structural features of piRNAs and their targets, their role in epigenetic regulation, and their potential influence on congenital diseases, it is clear from this symposium's talks that piRNAs play a crucial role in guarding the germline.
Use the tabs above to find a meeting report and multimedia from this event.
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Eric Lai, PhD
Eric Lai received his BA from Harvard University and performed thesis work in the laboratory of Gary Ruvkun, where he learned about developmental gene regulation in C. elegans. He did his PhD at UC San Diego with James Posakony on Drosophila neural patterning and Notch signaling, and continued to study these topics as a postdoc with Gerald Rubin at UC Berkeley. He joined the faculty of Sloan–Kettering Institute in 2005. His laboratory studies diverse topics related to developmental gene control at both transcriptional and post-transcriptional levels.
Marta Murcia, PhD
The New York Academy of Sciences
Stefan Ameres, PhD
Stefan Ameres studied biology at Friedrich-Alexander University Erlangen–Nuremberg, Germany. He did his PhD at the Max F. Perutz Laboratories in Vienna, Austria where he studied the molecular basis for target RNA recognition by small RNAs in the laboratory of Renée Schroeder. Now, Ameres works as a postdoc with Phillip Zamore at the University of Massachusetts Medical School, where he studies regulatory aspects of RNA silencing pathways in Drosophila and mammals.
Weifeng Gu, PhD
Weifeng Gu received his MD from Peking University Health Science Center (previously known as Beijing Medical University), where he studied human chemokines. He did his PhD at University of Rochester with Eric Phizicky studying tRNA modification. Then he went to UMass Medical school to work with Craig Mello as a postdoc to study endogenous small RNAs in C. elegans.
Nelson Lau, PhD
Nelson Lau is an assistant professor of biology at Brandeis University, and his laboratory studies gene and genome regulatory processes controlled by small RNAs. Lau obtained a PhD from MIT where he worked with David Bartel, and hewas a Whitney Foundation Fellow in Robert Kingston's lab at Massachusetts General Hospital, where he discovered piRNAs from rats and mice. Lau is a 2010 Searle Scholar and a recipient of an NIH K99 award.
Haifan Lin, PhD
Haifan Lin is Professor of Cell Biology and Director of the Yale Stem Cell Center at the Yale University School of Medicine. Lin's research has greatly strengthened understanding of the molecular mechanisms that define the unique behavior of stem cells. His early contributions include identification of stem cells in the Drosophila ovary and establishment of these stem cells as an effective model for study. Lin has discovered key genes involved in both niche signaling and intracellular regulation, most notably the piwi/argonaute gene family. His work on Piwi proteins lead to the discovery of a group of small RNAs called PIWI-interacting, or piRNAs. The discovery of piRNAs independently by Lin and others was recognized by Science Magazine as a top scientific breakthrough of 2006. Currently, the Lin lab is exploring the role of these molecules in epigenetic and posttranscriptional regulation of gene expression.
Zissimos Mourelatos, MD
Zissimos Mourelatos obtained his MD from the Aristotelian University, Greece in 1991. From 1991 to 1995 he was research fellow in the laboratory of Nicholas Gonatas at PENN, studying the cell biology of the Golgi apparatus in neurons and in motor neuron diseases. From 1995 to 1998 he was resident in Anatomic Pathology and clinical fellow in Neuropathology. From 1998 to 2002 he was postdoctoral fellow in the laboratory of Gideon Dreyfuss at PENN. Since 2002 he is a faculty member of the Department of Pathology & Laboratory Medicine at PENN. His laboratory investigates the basic biology of small regulatory RNPs and also how RNA dysregulation contributes to neurodegeneration. He is also a practicing surgical neuropathologist and the director of Neuropathology at PENN.
Priya Rajasethupathy attended Cornell University for her undergraduate studies, and majored in Biological Sciences. She received her BA degree and graduated Suma Cum Laude from Cornell in 2004. She then traveled to India and spent one year as a research student at the National Center for Biological Sciences in Bangalore, India. Upon returning, she joined the MD–PhD program at Columbia University, where she is currently pursuing her PhD in neuroscience with Eric Kandel.
Haruhiko Siomi, PhD
Haruhiko Siomi has obtained his Diploma degree (1982) and MS degree (1984) in Chemistry ('sugar chemistry') at Gifu University, and his PhD (1988) in virology ('HTLV1') at the Institute for Virus Research in Kyoto University. He joined the Gideon Dreyfuss laboratory in the Department of Biochemistry and Biophysics at the University of Pennsylvania School of Medicine as a HHMI associate in May 1990 and later promoted to Research Assistant Professor ('hnRNPs and FMR1'). In 1999, he became a Professor in the Institute for Genome Research at the University of Tokushima. He then moved to Keio University School of Medicine as Professor in Department of Molecular Biology in 2008. His laboratory investigates various aspects of RNA silencing.
Zev Williams, MD
Zev Williams is a research associate in the laboratory of Dr. Thomas Tuschl at Rockefeller University and a senior fellow in reproductive endocrinology and infertility at Weill–Cornell Medical Center. He received his MD and PhD degrees from the Mount Sinai School of Medicine with Dr. Paul Wassarman where he studied the biosynthesis and assembly of the mammalian egg coat. He continued his studies on the molecular biology of the oocyte through his residency in Obstetrics and Gynecology at the Brigham and Women's Hospital and Massachusetts General Hospital.
Keith Mulvihill is a freelance writer based in Manhattan. He worked as an environmental chemist before becoming a science writer. He covers a wide range of topics and has contributed to a variety of newspapers, magazines and websites.