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Maria Dominguez

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Papers by Maria Dominguez

Research paper thumbnail of Agrupaciones mercantiles --restricciones legales

Research paper thumbnail of Growth and specification of the eye are controlled independently by Eyegone and Eyeless in Drosophila melanogaster

Nature Genetics, 2003

Control of growth determines the size and shape of organs. Localized signals known as 'organizers... more Control of growth determines the size and shape of organs. Localized signals known as 'organizers' and members of the Pax family of proto-oncogenes are both elements in this control. Pax proteins have a conserved DNA-binding paired domain, which is presumed to be essential for their oncogenic activity. We present evidence that the organizing signal Notch does not promote growth in eyes of D. melanogaster through either Eyeless (Ey) or Twin of eyeless (Toy), the two Pax6 transcription factors. Instead, it acts through Eyegone (Eyg), which has a truncated paired domain, consisting of only the C-terminal subregion. In humans and mice, the sole PAX6 gene produces the isoform PAX6(5a) by alternative splicing; like Eyegone, this isoform binds DNA though the C terminus of the paired domain. Overexpression of human PAX6(5a) induces strong overgrowth in vivo, whereas the canonical PAX6 variant hardly effects growth. These results show that growth and eye specification are subject to independent control and explain hyperplasia in a new way.

Research paper thumbnail of Epigenetic silencers and Notch collaborate to promote malignant tumours by Rb silencing

Nature, 2006

Cancer is both a genetic and an epigenetic disease. Inactivation of tumour-suppressor genes by ep... more Cancer is both a genetic and an epigenetic disease. Inactivation of tumour-suppressor genes by epigenetic changes is frequently observed in human cancers, particularly as a result of the modifications of histones and DNA methylation. It is therefore important to understand how these damaging changes might come about. By studying tumorigenesis in the Drosophila eye, here we identify two Polycomb group epigenetic silencers, Pipsqueak and Lola, that participate in this process. When coupled with overexpression of Delta, deregulation of the expression of Pipsqueak and Lola induces the formation of metastatic tumours. This phenotype depends on the histone-modifying enzymes Rpd3 (a histone deacetylase), Su(var)3-9 and E(z), as well as on the chromodomain protein Polycomb. Expression of the gene Retinoblastoma-family protein (Rbf) is downregulated in these tumours and, indeed, this downregulation is associated with DNA hypermethylation. Together, these results establish a mechanism that links the Notch-Delta pathway, epigenetic silencing pathways and cell-cycle control in the process of tumorigenesis.

Research paper thumbnail of Auditoría y Dictamen fiscal 21 NIF B -10 Efectos de la inflación

A partir del 1º de enero de este 2008, entró en vigor la nueva norma de información financiera (N... more A partir del 1º de enero de este 2008, entró en vigor la nueva norma de información financiera (NIF) B -10 Efectos de la Inflación, en este documento mencionaremos los principales conceptos y elementos de esta norma.

Research paper thumbnail of Agrupaciones mercantiles --restricciones legales

Research paper thumbnail of Growth and specification of the eye are controlled independently by Eyegone and Eyeless in Drosophila melanogaster

Nature Genetics, 2003

Control of growth determines the size and shape of organs. Localized signals known as 'organizers... more Control of growth determines the size and shape of organs. Localized signals known as 'organizers' and members of the Pax family of proto-oncogenes are both elements in this control. Pax proteins have a conserved DNA-binding paired domain, which is presumed to be essential for their oncogenic activity. We present evidence that the organizing signal Notch does not promote growth in eyes of D. melanogaster through either Eyeless (Ey) or Twin of eyeless (Toy), the two Pax6 transcription factors. Instead, it acts through Eyegone (Eyg), which has a truncated paired domain, consisting of only the C-terminal subregion. In humans and mice, the sole PAX6 gene produces the isoform PAX6(5a) by alternative splicing; like Eyegone, this isoform binds DNA though the C terminus of the paired domain. Overexpression of human PAX6(5a) induces strong overgrowth in vivo, whereas the canonical PAX6 variant hardly effects growth. These results show that growth and eye specification are subject to independent control and explain hyperplasia in a new way.

Research paper thumbnail of Epigenetic silencers and Notch collaborate to promote malignant tumours by Rb silencing

Nature, 2006

Cancer is both a genetic and an epigenetic disease. Inactivation of tumour-suppressor genes by ep... more Cancer is both a genetic and an epigenetic disease. Inactivation of tumour-suppressor genes by epigenetic changes is frequently observed in human cancers, particularly as a result of the modifications of histones and DNA methylation. It is therefore important to understand how these damaging changes might come about. By studying tumorigenesis in the Drosophila eye, here we identify two Polycomb group epigenetic silencers, Pipsqueak and Lola, that participate in this process. When coupled with overexpression of Delta, deregulation of the expression of Pipsqueak and Lola induces the formation of metastatic tumours. This phenotype depends on the histone-modifying enzymes Rpd3 (a histone deacetylase), Su(var)3-9 and E(z), as well as on the chromodomain protein Polycomb. Expression of the gene Retinoblastoma-family protein (Rbf) is downregulated in these tumours and, indeed, this downregulation is associated with DNA hypermethylation. Together, these results establish a mechanism that links the Notch-Delta pathway, epigenetic silencing pathways and cell-cycle control in the process of tumorigenesis.

Research paper thumbnail of Auditoría y Dictamen fiscal 21 NIF B -10 Efectos de la inflación

A partir del 1º de enero de este 2008, entró en vigor la nueva norma de información financiera (N... more A partir del 1º de enero de este 2008, entró en vigor la nueva norma de información financiera (NIF) B -10 Efectos de la Inflación, en este documento mencionaremos los principales conceptos y elementos de esta norma.

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