The mechanisms that govern the repression of 5-HT1A receptor gene expression mediated by a novel mental retardation gene, Freud-1, were examined in HEK293 and SKNSH cells. This study provides a possible mechanism of 5-HT1A receptor gene regulation by Freud-1, which, to mediate its action, recruits Swi/Snf and Sin3A/histone deacetylase (HDAC) complexes in non-neuronal HEK293 cells and Swi/Snf only in neuronal, 5-HT1A receptor-expressing SKNSH cells. Thus, Freud-1 has a dual mechanism of repression depending on cell type: HDAC dependent in HEK293 cells and HDAC independent in SKNSH cells. In addition, I present evidence that Freud-1 is not sumoylated at its consensus sumoylation sites and I present the lipid binding properties of Freud-1 and Freud-1 mutants.

The mechanisms that govern the repression of 5-HT1A receptor gene expression mediated by a novel mental retardation gene, Freud-1, were examined in HEK293 and SKNSH cells. This study provides a possible mechanism of 5-HT1A receptor gene regulation by Freud-1, which, to mediate its action, recruits Swi/Snf and Sin3A/histone deacetylase (HDAC) complexes in non-neuronal HEK293 cells and Swi/Snf only in neuronal, 5-HT1A receptor-expressing SKNSH cells. Thus, Freud-1 has a dual mechanism of repression depending on cell type: HDAC dependent in HEK293 cells and HDAC independent in SKNSH cells. In addition, I present evidence that Freud-1 is not sumoylated at its consensus sumoylation sites and I present the lipid binding properties of Freud-1 and Freud-1 mutants.

The mechanisms that govern the repression of 5-HT1A receptor gene expression mediated by a novel mental retardation gene, Freud-1, were examined in HEK293 and SKNSH cells. This study provides a possible mechanism of 5-HT1A receptor gene regulation by Freud-1, which, to mediate its action, recruits Swi/Snf and Sin3A/histone deacetylase (HDAC) complexes in non-neuronal HEK293 cells and Swi/Snf only in neuronal, 5-HT1A receptor-expressing SKNSH cells. Thus, Freud-1 has a dual mechanism of repression depending on cell type: HDAC dependent in HEK293 cells and HDAC independent in SKNSH cells. In addition, I present evidence that Freud-1 is not sumoylated at its consensus sumoylation sites and I present the lipid binding properties of Freud-1 and Freud-1 mutants.

The mechanisms that govern the repression of 5-HT1A receptor gene expression mediated by a novel mental retardation gene, Freud-1, were examined in HEK293 and SKNSH cells. This study provides a possible mechanism of 5-HT1A receptor gene regulation by Freud-1, which, to mediate its action, recruits Swi/Snf and Sin3A/histone deacetylase (HDAC) complexes in non-neuronal HEK293 cells and Swi/Snf only in neuronal, 5-HT1A receptor-expressing SKNSH cells. Thus, Freud-1 has a dual mechanism of repression depending on cell type: HDAC dependent in HEK293 cells and HDAC independent in SKNSH cells. In addition, I present evidence that Freud-1 is not sumoylated at its consensus sumoylation sites and I present the lipid binding properties of Freud-1 and Freud-1 mutants.

As alterações cromossômicas estruturais associadas a fenótipos clínicos oferecem a oportunidade de identificação de genes cujas mutações possam estar determinando essas patologias, tendo em vista a possibilidade de que esses genes podem ter sido alterados pelas quebras ou ter o número de cópias modificado. Um número cada vez maior de evidências aponta para a participação de certas seqüências do genoma na formação de rearranjos cromossômicos recorrentes e não recorrentes. Neste trabalho, estudamos duas deleções cromossômicas detectadas em indivíduos com retardo mental associado a sinais clínicos. O objetivo foi determinar que mecanismos originaram esses rearranjos e como a perda ou quebra dos segmentos cromossômicos está relacionada com o fenótipo dos portadores. A caracterização das seqüências nos pontos de quebra e junção desses rearranjos é fundamental para a compreensão dos mecanismos de formação das alterações cromossômicas. A delimitação precisa dos segmentos deletados é necessária para a correlação com o quadro clínico. Para isso, este trabalho aliou o estudo cromossômico por hibridação in situ fluorescente (FISH) à análise do DNA. / Structural chromosomal alterations related to clinical phenotypes bring the opportunity to identify gene mutations determining the pathologies, because the causative genes may have been disrupted by the breaks or may have an altered number of copies. The delimitation of the segments involved in the chromosomal rearrangements is necessary for these genotype-phenotype correlations. The characterization of breakpoint and junction sequences in these chromosome alterations enables the identification of mechanisms originating them, and evidence has been produced pointing to the participation of particular genomic sequences in their formation. In this work, we studied two chromosomal deletions in patients with syndromic mental retardation, combining chromosomal analysis by fluorescent in situ hybridization (FISH) to DNA analysis. Our aim was to determine the mechanisms that originated these aberrations and how they were involved with the clinical phenotypes.

As alterações cromossômicas estruturais associadas a fenótipos clínicos oferecem a oportunidade de identificação de genes cujas mutações possam estar determinando essas patologias, tendo em vista a possibilidade de que esses genes podem ter sido alterados pelas quebras ou ter o número de cópias modificado. Um número cada vez maior de evidências aponta para a participação de certas seqüências do genoma na formação de rearranjos cromossômicos recorrentes e não recorrentes. Neste trabalho, estudamos duas deleções cromossômicas detectadas em indivíduos com retardo mental associado a sinais clínicos. O objetivo foi determinar que mecanismos originaram esses rearranjos e como a perda ou quebra dos segmentos cromossômicos está relacionada com o fenótipo dos portadores. A caracterização das seqüências nos pontos de quebra e junção desses rearranjos é fundamental para a compreensão dos mecanismos de formação das alterações cromossômicas. A delimitação precisa dos segmentos deletados é necessária para a correlação com o quadro clínico. Para isso, este trabalho aliou o estudo cromossômico por hibridação in situ fluorescente (FISH) à análise do DNA. / Structural chromosomal alterations related to clinical phenotypes bring the opportunity to identify gene mutations determining the pathologies, because the causative genes may have been disrupted by the breaks or may have an altered number of copies. The delimitation of the segments involved in the chromosomal rearrangements is necessary for these genotype-phenotype correlations. The characterization of breakpoint and junction sequences in these chromosome alterations enables the identification of mechanisms originating them, and evidence has been produced pointing to the participation of particular genomic sequences in their formation. In this work, we studied two chromosomal deletions in patients with syndromic mental retardation, combining chromosomal analysis by fluorescent in situ hybridization (FISH) to DNA analysis. Our aim was to determine the mechanisms that originated these aberrations and how they were involved with the clinical phenotypes.