INVESTIGADORES
SILVA JUNQUEIRA DE SOUZA Flavio
congresos y reuniones científicas
Título:
Functional Comparative Genomics at the Vertebrate Extremes
Autor/es:
DOMENE S; DE SOUZA FS; BUMASCHNY VF; NASIF S; RUBINSTEIN M
Lugar:
San Miguel de Tucumán
Reunión:
Congreso; XLV Reunion anual de la Sociedad Argentina de Investigacion en Bioquimica y Biologia Molecular; 2009
Resumen:
Until
recently, the identification of transcriptional enhancers has relied on
tedious deletional studies of non coding flanking regions
systematically tested in expression assays. The near completion of
several vertebrate genomes has dynamized this task by revealing a myriad
of conserved potential cis-acting elements such as the neuron-specific
enhancers of the proopiomelanocortin gene (Pomc), nPE1 and nPE2, that we
discovered to be conserved across mammals. To study the molecular
evolution of Pomc expression we analyzed the ability of putative
enhancer sequences to drive reporter gene expression to transgenic
animals of distant vertebrate Orders: the mammal Mus musculus (mouse)
and the teleost fish Danio rerio (zebrafish). To this end, we set up a
transgenic zebrafish facility and determined that mouse nPE1 and nPE2
were able to drive EGFP expression to the hypothalamus of transgenic
zebrafish embryos. Using the tol2 transposon system, we injected
zebrafish eggs with ptol2-nPE1-nPE2-zpomca-egfp and
ptol2ÄnPE1-nPE2-zpomca-egfp. Interestingly, both constructs drove EGFP
expression to the pituitary and hypothalamus of zebrafish embryos and
EGFP colocalized within Pomc neurons as determined by immunofluorescence
against ACTH. These results provide a clear example of functional
conservation at the vertebrate extremes despite great sequence
divergence.