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Structural & Cellular Biology
Tulane University School of Medicine
Box SL49, Room 3004
1430 Tulane Avenue
New Orleans, Louisiana 70112
Telephone: (504) 988-5255
Fax: (504) 988-1687
Victoria P. Belancio, Ph.D.

belancioAssistant Professor

vperepe@tulane.edu

Research Interests:

Only a small proportion of the human genome actually codes for proteins, begging the question of what the rest of our genetic material actually does.  Human retrotransposons, long dismissed as inert repetitive sequences of "junk DNA," are quite active and can profoundly influence our genomes.  Our lab studies one type of these sequences, termed Long Interspersed Element 1 (LINE1 or L1 for short).  Through the use of its two proteins encoded in its bicistronic mRNA (ORF1p and ORF2p), L1 is able to copy and paste itself into new genomic locations.  L1 proteins (particularly ORF2p, which contains two enzymatic functions endonuclease and reverse transcriptase) are also used by other parasitic elements (SINEs, Short Interspersed Elements, and SVA) to move about the genome. Furthermore, L1 machinery is responsible for the generation of processed pseudogenes. L1 is thus the direct and indirect progenitor of a sizable chunk of our genome. Until recently, retrotransposition was believed to take place predominantly in the germ line. The current view is that L1 expression and retrotransposition also occurs in somatic cells, with tumors being particularly permissive for L1 activity.  

Retrotransposition is only one of (albeit the best studied) ways L1 can damage our genome. L1 ORF2p, through its endonuclease, can induce DNA double strand breaks that can introduce a spectrum of mutations if not repaired faithfully, trigger cellular senescence, or even lead to apoptotic cell death.

L1, SINE, and SVA sequences can influence gene function and genome organization long after integration by bringing along their functional promoters, polyadenylation signals, and splice sites; usage of which can alter gene expression or generate novel chimeric transcripts. Additionally, all repetitive sequences can undergo homologous recombination, leading to deletion or duplication of genetic material which can at times be mutagenic. Over the course of evolution, the human genome accumulated a staggering 500,000 copies of L1 and over 1,000,000 copies of the human SINE Alu. Fortunately for our cells, most of these loci are inactive. However,  non-allelic homologous recombination between these highly-related  sequences still causes a wide spectrum of human diseases.

Despite its ubiquity and evolutionary influence, many details of L1 replication cycle,  as well as the  basic functions and interaction profiles of the L1 proteins remain unknown.  Our lab is working to elucidate some of these unknowns from a number of angles and fronts.  Our research interests are focused on the contribution of L1 to human disease (particularly cancer and other age-associated diseases) and include:

  • the RNA and protein biology of L1 as well as the influence of the circadian system (how cells in a complex organism tell time) on L1 activity
  • characterization of the cytotoxic properties of the ORF2p endonuclease domain and cellular response to L1 activity
  • characterization of L1 protein expression and regulation in the mammalian environment

Our lab is unique in that we employ a wide array of basic science strategies to study the L1 replication cycle, from basic molecular biology all the way unto animal models. We routinely perform DNA, RNA,and protein analyses, in addition to tissue culture-based experiments and Next Generation Sequencing approaches.

My lab is a part of the Tulane Cancer Center, Tulane Circadian Cancer Biology group, and COMET, the Consortium of Transposable Elements at Tulane.  If you would like more specifics on any of our many projects, please do not hesitate to contact me.

Education:

Cytology and Genetics Novosibirsk State University, Novosibirsk, Russia
Medical Genetics UAB, Birmingham, AL
Molecular and Cellular Biology  Tulane University, New Orleans, LA

Selected Publications:

  1. Perepelitsa-Belancio V, Deininger P. RNA truncation by premature polyadenylation attenuates human mobile element activity. Nat Genetics. Dec; 35(4):363-6. 2003 [commentaries in ‘The Scientist’ and ‘Nature Reviews Genetics’] PMID:14625551
  2. Belancio VP., Hedges DJ., Deininger P. LINE-1 RNA splicing and influences on mammalian gene expression. Nucleic Acid Research. Mar 22; 34(5):1512-1521 2006  PMID:16554555
  3. Belancio VP., Roy-Engel AM., Pochampally RR., and Deininger P. Somatic expression of  LINE-1 elements in human tissues. Nucleic Acid Research. Jul 1;38(12):3909-22, 2010 PMID:20215437
  4. Belancio VP., Roy-Engel A., and Deininger. P. All y’all need to know ‘bout retroelements in cancer. Seminars in Cancer Biology. Invited review. Aug;20(4):200-10 2010 PMID:20600922
  5. Belancio VP. Importance of RNA analysis in interpretation of reporter gene expression data. Analytical Biochemistry. Oct 1;417(1):159-61. 2011 PMID:21693100
  6. Belancio VP. and Roy-Engel AM. Modulation of Human Mobile Elements and Genetic Instability by Environmental Factors. (article 241) In Nriagu JO (ed): Encyclopedia of Environmental Health, volume 3, p831-839 Burlington: Elsevier, 2011 http://media.matthewsbooks.com.s3.amazonaws.com/documents/tocwork/044/9780444522733.pdf
  7. Roy-Engel AM. and Belancio VP., Retrotransposons and human disease. Encyclopedia of Life Sciences, Cooper D. Scientific Editor for Genetics and Disease, John Wiley & Sons Ltd Advisory Editor, Genomic Medicine. Invited review. 2011  http://onlinelibrary.wiley.com/doi/10.1002/9780470015902.a0005492.pub2/abstract
  8. Hedges D. and Belancio VP. Restless Genomes: humans as a model organism for understanding host-retrotransposable element dynamics. Advances in Genetics. 73:219-62, 2011 PMID:21310298
  9. Dauchy RT., Dauchy EM., Mau L., Belancio VP., Hill SM., and Blask DE. A New Apparatus and Surgical Technique for the Dual Perfusion of Tissue-Isolated Human Tumor Xenografts in Situ in Nude Rats. Journal of Comparative Medicine. Apr 62 (2):99-108 (10), 2012
  10. Kines KJ. and Belancio VP. Expressing genes do not forget their LINEs: transposable elements and gene expression. Invited review. Frontiers in Biosciences, Jan 1;17:1329-1344. 2012 PMID:22201807
  11. Sokolowski M., deHaro D., Kines KJ., Christian C., Belancio VP. Characterization of self-interaction and cellular localization of L1 ORF1p using mammalian two hybrid system. PLoS ONE. December 4, 8(12): e82021., 2013
  12. deHaro DL., Kines KJ., Sokolowski M., Dauchy RT., Streva VA., Hill SM., Hanifin JP., Brainard GC., Blask DE., Belancio VP., “Regulation of L1 expression and retrotransposition by melatonin and its receptor; implications for cancer risk associated with light exposure at night". Nucleic Acids Research.  Aug 1;42(12):7694-707, 2014
  13. Kines KJ., Sokolowski M., Christian C., deHaro D., Belancio VP.  Potential for genomic instability associated with retrotranspositionally-incompetent L1 loci. Nucleic Acids Research.  (in press) 2014
  14. Blask DE., Dauchy RT., Dauchy E., Mao L., Hill SM., Greene M., Belancio VP., Sauer LA., Davidson L.  Light exposure at night disrupts host/cancer circadian regulatory dynamics: impact on the Warburg effect, lipid signaling and tumor growth prevention. PLoS ONE Aug 6;9(8), 2014

Invited Talks:

  1. Louisiana Healthy Aging Study Retreat, May 2-3, 2007 Gulf Shores, AL
  2. Tulane University Hayward Genetics Center seminar series, December, 2007
  3. Tulane University Center for Aging, March, 2008
  4. The National Institute on Aging Directors Regional Meeting on Aging Research, New Orleans, April, 2009
  5. Division of Aging Biology New Investigator Forum, Bethesda, MD, May 2009
  6. Louisiana Cancer Research Consortium annual retreat, New Orleans, LA, April 2010
  7. Tulane University, Department of Pathology, New Orleans, LA, May 2010
  8. Louisiana State University, Department of Pharmacology, New Orleans, LA, June, 2010
  9. Tulane University, Center for Aging, New Orleans, LA, October 2010
  10. Melatonin Receptors: Action and Therapeutics. FASEB 2011 Summer Research Conference, Snowmass, CO, June26-July 1, 2011
  11. Mobile DNA and Mammalian Genomes. FASEB 2011 Summer Research Conference, Snowmass, CO, August 7-12, 2011
  12. Louisiana State University, Department of Biochemistry and Molecular Biology, New Orleans, LA, December 9, 2011
  13. International Conference on Transposable Elements (ICTE2012), St-Malo, France, April 21-24, 2012. (short talk)
  14. A New Horizon of Retrotransposon Research,  International Symposium, Kyoto, Japan, July 31-August 4, 2012
  15. The Biology of Aging Colloquium, Ellison Medical Foundation, Woods Hole, MA, August, 2012
  16. Aging and Disease of Aging, Keystone Symposia on Molecular Biology, Tokyo, Japan October, 2012 (short talk)
  17. Mobile DNA and Mammalian Genomes. FASEB 2013 Summer Research Conference, Big Sky, MO, June 7-14, 2013
  18. Transposition and Genome Engineering. Budapest, Hungary, September 18-22, 2013(short talk)

Honors and Awards:

Louisiana Cancer Research Consortium Award for Outstanding Scientific Achievement in the Genetics program, 2010
Research highlighted in Tulane Cancer Center Breakthroughs 2009 spring issue
Research highlighted in Tulane Cancer Center Breakthroughs 2013 spring issue

Kavli fellow, the U. S. National Academy of Science and Alexander von Humboldt Foundation 18th annual German-American Kavli Frontiers of Science symposium
, Potsdam, Germany, May 10-13, 2012 (by invitation only)

Director of the Tulane Cancer Center seminar series
http://tulane.edu/som/cancer/research/tulane-cancer-center-lcrc-seminar-series.cfm
 

Member:

COMET (Consortium of Transposable Elements at Tulane)

Tulane Cancer Center
http://tulane.edu/som/cancer/research/people/victoria-p-belancio.cfm

Tulane Circadian Cancer Biology Group
http://tulane.edu/som/departments/scb/CCBG/members.cfm

Tulane Center for Aging
http://tulane.edu/som/aging/mission-vision.cfm

Tulane University School of Medicine, Dept. of SCB, New Orleans, LA 70112 504-988-5255 tfrasch@tulane.edu