RESUMO
In the last decade, there has been a flood of new technology in the sequencing arena. The onset of next-generation sequencing (NGS) technology has resulted in the vast increase in genetic diagnostic testing available to the ordering physician. Whole exome sequencing (WES) has become available as a diagnostic test performed in certified clinical laboratories. This has led to increased presence in the diagnostic marketplace, increased consumer awareness, and the question has been raised by various stakeholders to whether there is sufficient stringent regulation of WES and other NGS-based tests. We discuss the various WES services currently available in the marketplace, current regulation of WES as a laboratory developed test, the proposed FDA involvement in its oversight as well as the response of various laboratory groups that provide these diagnostic services. Overall, a rigorous process oversight and assessment of inter-lab reproducibility is strongly warranted for WES as it is used as a diagnostic test, but regulation should be mindful of the excessive administrative burden on academic and smaller diagnostic laboratories.
Assuntos
Testes Diagnósticos de Rotina , Exoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Patologia Molecular/tendências , Testes Genéticos , Genoma Humano , HumanosRESUMO
Little is known about how mammalian cells maintain cell size homeostasis. We conducted a novel genetic screen to identify cell-size-controlling genes and isolated Largen, the product of a gene (PRR16) that increased cell size upon overexpression in human cells. In vitro evidence indicated that Largen preferentially stimulates the translation of specific subsets of mRNAs, including those encoding proteins affecting mitochondrial functions. The involvement of Largen in mitochondrial respiration was consistent with the increased mitochondrial mass and greater ATP production in Largen-overexpressing cells. Furthermore, Largen overexpression led to increased cell size in vivo, as revealed by analyses of conditional Largen transgenic mice. Our results establish Largen as an important link between mRNA translation, mitochondrial functions, and the control of mammalian cell size.
Assuntos
Tamanho Celular/efeitos dos fármacos , Regulação da Expressão Gênica , Biossíntese de Proteínas , Proteínas/genética , RNA Mensageiro/genética , Animais , Linhagem Celular Tumoral , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos , Ensaios de Triagem em Larga Escala , Humanos , Células Jurkat , Camundongos , Camundongos Transgênicos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Retroviridae/genética , Retroviridae/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologiaRESUMO
We used DNA microarray screening to identify Ckap2 (cytoskeleton associated protein 2) as a novel p53 target gene in a mouse erythroleukemia cell line. DNA damage induces human and mouse CKAP2 expression in a p53-dependent manner and p53 activates the Ckap2 promoter. Overexpressed Ckap2 colocalizes with and stabilizes microtubules. In p53-null cells, overexpression of Ckap2 induces tetraploidy with aberrant centrosome numbers, suggesting disturbed mitosis and cytokinesis. In p53-competent cells, Ckap2 does not induce tetraploidy but activates p53-mediated cell cycle arrest and apoptosis. Our data suggest the existence of a functional positive feedback loop in which Ckap2 activates the G1 tetraploidy checkpoint and prevents aneuploidy.