RESUMO
RNA has been classically known to play central roles in biology, including maintaining telomeres, protein synthesis, and in sex chromosome compensation. While thousands of long noncoding RNAs (lncRNAs) have been identified, attributing RNA-based roles to lncRNA loci requires assessing whether phenotype(s) could be due to DNA regulatory elements, transcription, or the lncRNA. Here, we use the conserved X chromosome lncRNA locus Firre, as a model to discriminate between DNA- and RNA-mediated effects in vivo. We demonstrate that (i) Firre mutant mice have cell-specific hematopoietic phenotypes, and (ii) upon exposure to lipopolysaccharide, mice overexpressing Firre exhibit increased levels of pro-inflammatory cytokines and impaired survival. (iii) Deletion of Firre does not result in changes in local gene expression, but rather in changes on autosomes that can be rescued by expression of transgenic Firre RNA. Together, our results provide genetic evidence that the Firre locus produces a trans-acting lncRNA that has physiological roles in hematopoiesis.
Assuntos
Loci Gênicos , Hematopoese/genética , RNA Longo não Codificante/genética , Animais , Fertilidade/genética , Regulação da Expressão Gênica no Desenvolvimento , Imunidade Inata/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Camundongos Knockout , Especificidade de Órgãos/genética , Fenótipo , RNA Longo não Codificante/metabolismoRESUMO
Upon the premature loss of permanent anterior teeth from unanticipated trauma or by ongoing patient neglect requiring surgery, patient requisites of functional and esthetic considerations must be addressed. Interim management can be achieved through the use of several diverse fixed and/or removable treatment modalities. The purposes of this report are to provide a review of traditional and unconventional techniques for interim replacement of missing anterior teeth and to present a clinical report demonstrating the fabrication of a removable, thermoplastic (vacuum-formed) EssixTM prosthesis, utilizing composite resin as the surrogate material of choice for the absent teeth. This measure proved to be an immediate, esthetic, and transitional treatment solution prior to a permanent resolution for the patient's long-term dental requirements.