RESUMO
Retroviral integrase (IN) proteins catalyze the permanent integration of proviral genomes into host DNA with the help of cellular cofactors. Lens epithelium-derived growth factor (LEDGF) is a cofactor for lentiviruses, including human immunodeficiency virus type 1 (HIV-1), and targets lentiviral integration toward active transcription units in the host genome. In contrast to lentiviruses, murine leukemia virus (MLV), a gammaretrovirus, tends to integrate near transcription start sites. Here, we show that the bromodomain and extraterminal domain (BET) proteins BRD2, BRD3, and BRD4 interact with gammaretroviral INs and stimulate the catalytic activity of MLV IN in vitro. We mapped the interaction site to a characteristic structural feature within the BET protein extraterminal (ET) domain and to three amino acids in MLV IN. The ET domains of different BET proteins stimulate MLV integration in vitro and, in the case of BRD2, also in vivo. Furthermore, two small-molecule BET inhibitors, JQ1 and I-BET, decrease MLV integration and shift it away from transcription start sites. Our data suggest that BET proteins might act as chromatin-bound acceptors for the MLV preintegration complex. These results could pave a way to redirecting MLV DNA integration as a basis for creating safer retroviral vectors.
Assuntos
Cromatina/metabolismo , Vírus da Leucemia Murina/fisiologia , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Ligação a RNA/metabolismo , Infecções por Retroviridae/metabolismo , Fatores de Transcrição/metabolismo , Integração Viral , Motivos de Aminoácidos , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Células HEK293 , Humanos , Integrases/genética , Integrases/metabolismo , Vírus da Leucemia Murina/enzimologia , Vírus da Leucemia Murina/genética , Camundongos , Proteínas Nucleares/química , Proteínas Nucleares/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Infecções por Retroviridae/genética , Infecções por Retroviridae/virologia , Fatores de Transcrição/química , Fatores de Transcrição/genética , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
The rehabilitation services for children with cerebral palsy are provided in two forms: home-based care and center-based care. The aim of this research was to evaluate the cost-effectiveness of the home-based accordance with the center-based care for kids with cerebral palsy. In this cost-effectiveness research, 56 children under 12 years old were assigned randomly to two rehabilitation programs: (1) clinic-based rehabilitation services (CBRS); and (2) home-based rehabilitation services (HBRS). Data were collected by two questionnaires: a strong life quality survey of children with cerebral palsy (CP QOL-Child) and medical and non-medical costs' checklists. Finally, the incremental expense-efficacy rate (ICER) was used to determine the further expenses of one unit of the quality of life gained by CBRS compared with HBRS. The mean costs per patients for the home-based care group were less than the ones for the clinic-based care unit (US$ 660.3 vs. US$ 933.8). The costs of the rehabilitation services and transportation were the main costs in the two patients' groups. The quality of life for cases in the home-based care group was better than the one of the clinic-based care team. The results showed that the home-based care method was more cost-effective than the centre-based care approach in children with cerebral palsy. The incremental cost-effectiveness ratio was calculated at about US$ 2.6. The conclusion was that home-based care centers were more cost-effective than the centre-based care centers for children with cerebral palsy. Therefore, it was suggested that the health policy makers pay more attention to developing home-based care strategy in physically challenged children.