RESUMO
Recent reports have demonstrated that mice lacking the transcription factor Cited2 die in utero showing various cardiac malformations. We present for the first time functionally relevant mutations of CITED2 in patients with congenital heart defects (CHDs). CITED2 encodes a CREBBP/EP300 interacting transcriptional modulator of HIF1A and TFAP2. To study the potential impact of sequence variations in CITED2 for CHDs in humans, we screened a cohort of 392 well-characterized patients and 192 control individuals using DHPLC, sequencing, and Amplifluor genotyping techniques. We identified 15 CITED2 nucleotide alterations. Seven of these alterations were found only in CHD patients and were not detected in controls, including three mutations leading to alterations of the amino acid sequence (p.Ser170_Gly178del, p.Gly178_Ser179ins9, and p.Ser198_Gly199del). All three of these amino acid changing mutations cluster in the serine-glycine-rich junction of the protein, to which no functionality had heretofore been assigned. Here we show that these mutations significantly reduce the capacity of CITED2 to transrepress HIF1A, and that the p.Ser170_Gly178del mutation significantly diminishes TFAP2C coactivation. This reveals a modifying role for the serine-glycine-rich region in CITED2 function. In summary, the observation of these mutations in patients with septal defects indicates that CITED2 has a causative impact in the development of CHD in humans.
Assuntos
Proteínas de Ligação a DNA/genética , Cardiopatias Congênitas/genética , Mutação , Proteínas Repressoras/genética , Transativadores/genética , Sequência de Aminoácidos , Linhagem Celular , Estudos de Coortes , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Frequência do Gene , Testes Genéticos , Haplótipos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteínas Recombinantes de Fusão/análise , Proteínas Repressoras/metabolismo , Proteínas Repressoras/fisiologia , Transativadores/metabolismo , Transativadores/fisiologia , Fator de Transcrição AP-2/genética , Fator de Transcrição AP-2/metabolismoRESUMO
BACKGROUND: Motivated by a biomedical database set up by our group, we aimed to develop a generic database front-end with embedded knowledge discovery and analysis features. A major focus was the human-oriented representation of the data and the enabling of a closed circle of data query, exploration, visualization and analysis. RESULTS: We introduce a non-task-specific database front-end with a new visualization strategy and built-in analysis features, so called d-matrix. d-matrix is web-based and compatible with a broad range of database management systems. The graphical outcome consists of boxes whose colors show the quality of the underlying information and, as the name suggests, they are arranged in matrices. The granularity of the data display allows consequent drill-down. Furthermore, d-matrix offers context-sensitive categorization, hierarchical sorting and statistical analysis. CONCLUSIONS: d-matrix enables data mining, with a high level of interactivity between humans and computer as a primary factor. We believe that the presented strategy can be very effective in general and especially useful for the integration of distinct data types such as phenotypical and molecular data.
