Neurogenetics, Development and Evolution





  Guillermo Oliver, Ph.D.

GUILLERMO OLIVER, Ph.D.

Associate Member
Department of Genetics and Tumor Cell Biology
St. Jude Children's Research Hospital
Affiliated Associate Professor
Department of Anatomy and Neurobiology
The University of Tennessee College of Medicine

Address

St. Jude Children's Research Hospital
MS 331, Room 3055
332 N. Lauderdale
Memphis, TN 38105
Tel: (901) 495-2697; Fax: (901) 495-2907;

Education

Ph.D. Institution: University of Uruguay, Montevideo, Uruguay

Research Interests

Long before most cells in the developing embryo begin to specialize, a plan is established that designates the major regions of the body: the head, trunk, tail, etc. Homeobox genes encoding nuclear transcriptions factors are major players during this process in metazoans since they specify the positions of cells and efficiently direct their fates. For the last ten years, Dr. Oliver has been interested in understanding the molecular links between morphogenetic fields, positional information, and homeobox genes in vertebrate development.

Six3 and eye development: Structural and functional conservation exists between homeobox genes in organisms as diverse as Drosophila and mouse. For example, despite the apparent differences in eye formation of vertebrates and arthropods, they both rely on a conserved developmental pathway, in which homeobox genes participate. The Drosophila homeobox gene sine oculis is crucial for eye development. Dr. Oliver's lab has cloned and characterized its murine homologue, Six3, which is expressed in the anterior neural plate and eye field. To examine whether Six3 participates in the process of eye formation, mouse Six3 was ectopically expressed in fish embryos and the results showed that Six3 is sufficient to promote ectopic lens formation in the area of the otic vesicle. To gain further insights into Six3 functions, they have recently inactivated this gene by homologous recombination in mice and are currently analyzing the phenotypic consequences of its lack of function. They will also pursue identifying those molecules that regulate Six3 expression in the early eye field, as well as the targets controlled by Six3 activity during early development. They anticipate that a greater understanding of Six3 function will further define the mechanisms and pathways involved in vertebrate eye development.

Prox 1: The product of the fly prospero gene is expressed in the lens-secreting cone cells. In mouse, we described the expression of its homologue, Prox1, in lens fibers, in the developing liver, pancreas, and neural crest. Its expression pattern suggests that Prox1 may participate in the cellular differentiation of various cell types. This assumption was confirmed by the observed phenotypes in their recently generated Prox1 null mice; most of the Prox1-expressing tissues are affected in these mice. They are complementing this analysis by generating different Prox1 transgenic mice and characterizing Prox1 regulatory elements.

Links

St Jude Faculty - Guillermo Oliver

Recent Publications

  • Geng X, Speirs C, Lagutin O, Inbal A, Liu W, Solnica-Krezel L, Jeong Y, Epstein DJ, Oliver G. Haploinsufficiency of Six3 fails to activate Sonic hedgehog expression in the ventral forebrain and causes holoprosencephaly. Dev Cell. 2008 Aug;15(2):236-47. PMID: 18694563
  • Oliver G, Srinivasan RS. Lymphatic vasculature development: current concepts. Ann N Y Acad Sci. 2008;1131:75-81. Review. PMID: 18519960
  • Lavado A, Lagutin OV, Oliver G. Six3 inactivation causes progressive caudalization and aberrant patterning of the mammalian diencephalon. Development. 2008 Feb;135(3):441-50. Epub 2007 Dec 19. PMID: 18094027
  • Srinivasan RS, Dillard ME, Lagutin OV, Lin FJ, Tsai S, Tsai MJ, Samokhvalov IM, Oliver G. Lineage tracing demonstrates the venous origin of the mammalian lymphatic vasculature. Genes Dev. 2007 Oct 1;21(19):2422-32. PMID: 17908929
  • Lavado A, Oliver G. Prox1 expression patterns in the developing and adult murine brain. Dev Dyn. 2007 Feb;236(2):518-24. PMID: 17117441
  • Geng X, Lavado A, Lagutin OV, Liu W, Oliver G. Expression of Six3 Opposite Strand (Six3OS) during mouse embryonic development. Gene Expr Patterns. 2007 Jan;7(3):252-7. Epub 2006 Sep 26. PMID: 17084678
view complete list of references (pubmed link)