RESUMEN
Studies of mammalian gene function are hampered by temporal limitations in which phenotypes occurring at one stage of development interfere with analysis at later stages. Moreover, phenotypes resulting from altered gene activity include both direct and indirect effects that may be difficult to distinguish. In the present study, recombinant fusion proteins bearing the 12 amino acid membrane translocation sequence (MTS) from the Kaposi fibroblast growth factor (FGF-4) were used to transduce enzymatically active Cre proteins directly into mammalian cells. High levels of recombination were observed in a variety of cultured cell types and in all tissues examined in mice following intraperitoneal administration. This represents the first use of protein transduction to induce the enzymatic conversion of a substrate in living cells and animals and provides a rapid and efficient means to manipulate mammalian gene structure and function.
Asunto(s)
Integrasas/genética , Transducción Genética , Proteínas Virales/genética , Animales , Diferenciación Celular , Línea Celular , Permeabilidad de la Membrana Celular , Células Cultivadas , Factor 4 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Integrasas/metabolismo , Ratones , Ratones Transgénicos , Estructura Terciaria de Proteína , Transporte de Proteínas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Virales/metabolismoRESUMEN
The gene FUS (also known as TLS (for translocated in liposarcoma) and hnRNP P2) is translocated with the gene encoding the transcription factor ERG-1 in human myeloid leukaemias. Although the functions of wild-type FUS are unknown, the protein contains an RNA-recognition motif and is a component of nuclear riboprotein complexes. FUS resembles a transcription factor in that it binds DNA, contributes a transcriptional activation domain to the FUS-ERG oncoprotein and interacts with several transcription factors in vitro. To better understand FUS function in vivo, we examined the consequences of disrupting Fus in mice. Our results indicate that Fus is essential for viability of neonatal animals, influences lymphocyte development in a non-cell-intrinsic manner, has an intrinsic role in the proliferative responses of B cells to specific mitogenic stimuli and is required for the maintenance of genomic stability. The involvement of a nuclear riboprotein in these processes in vivo indicates that Fus is important in genome maintenance.
