RESUMEN
Ubiquitin fold modifier 1 is a small ubiquitin-like protein modifier that is essential for embryonic development of metazoans. Although UFMylation has been connected to endoplasmic reticulum homeostasis, the underlying mechanisms and the relevant cellular targets are largely unknown. Here, we show that HRD1, a ubiquitin ligase of ER-associated protein degradation (ERAD), is a novel substrate of UFM1 conjugation. HRD1 interacts with UFMylation components UFL1 and DDRGK1 and is UFMylated at Lys610 residue. In UFL1-depleted cells, the stability of HRD1 is increased and its ubiquitination modification is reduced. In the event of ER stress, the UFMylation and ubiquitination modification of HRD1 is gradually inhibited over time. Alteration of HRD1 Lys610 residue to arginine impairs its ability to degrade unfolded or misfolded proteins to disturb protein processing in ER. These results suggest that UFMylation of HRD1 facilitates ERAD function to maintain ER homeostasis.
Asunto(s)
Estrés del Retículo Endoplásmico , Ubiquitina-Proteína Ligasas , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Estrés del Retículo Endoplásmico/fisiología , Proteínas/metabolismo , Retículo Endoplásmico/metabolismo , Ubiquitina/metabolismo , Homeostasis , Degradación Asociada con el Retículo EndoplásmicoRESUMEN
Obliterative bronchiolitis (OB) is characterized by sub-epithelial inflammatory and fibrotic narrowing of the bronchioles, and it is the predominant factor limiting long-term survival after lung transplantation. To explore molecular mechanism of OB, we investigated the interaction of transcription factor (TF), microRNA, long noncoding RNA (lncRNA), and gene expression in the mice model of OB by integrated analysis of TF array, miRNA microarray, and lncRNA and mRNA microarray. After 28 days of orthotopic tracheal transplantation in mice, 42 TFs were significantly up-regulated in allogeneic graft compared to syngeneic graft; 62 miRNAs including miR-376-5p were up-regulated and 17 miRNAs including miR-338-3p were down-regulated over 2-fold; 137 mRNAs were down-regulated and 129 mRNAs were up-regulated over 2-fold; 234 lncRNAs were up-regulated and 212 lncRNAs were down-regulated over 2-fold in the allogeneic model compared to that in the syngeneic control group. We further analyzed potential interaction between TFs, miRNAs, lncRNAs and target genes by different algorithms. Four differentially expressed TFs (Myc/Max, FOXO1, FOXM1, and SMAD) were predicted to regulate 3 different miRNAs, 17 mRNAs, and 16 lncRNAs. These findings suggest that modulation of altered transcription factors such as Myc/Max and FOXO1, and miRNAs such as miR-376-5p and miR-338-3p may become a preventive or therapeutic targets in the chronic lung allograft dysfunction.
Asunto(s)
Bronquiolitis Obliterante/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Tráquea/trasplante , Factores de Transcripción/genética , Animales , Bronquiolitis Obliterante/etiología , Bronquiolitis Obliterante/metabolismo , Bronquiolitis Obliterante/patología , Biología Computacional , Bases de Datos Genéticas , Modelos Animales de Enfermedad , Femenino , Proteína Forkhead Box M1 , Proteína Forkhead Box O1 , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Largo no Codificante/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo , Factores de Tiempo , Tráquea/metabolismo , Tráquea/patología , Factores de Transcripción/metabolismo , Trasplante Homólogo , Trasplante IsogénicoRESUMEN
Lung transplantation has already become the preferred treatment option for a variety of end-stage pulmonary failure. However the long-term results of lung transplantation are still not compelling and the major death reason is commonly due to obliterative bronchiolitis (OB) which is considered as chronic rejection presenting manifests physiologically as a progressive decline in FEV1. Transcription factors (TFs) play a key role in regulating gene expression and in providing an interconnecting regulatory between related pathway elements. Although the transcription factors are required for expression of the proinflammatory cytokines and immune proteins which are involved in obliterative bronchiolitis following lung transplantation, the alterations of the transcription factors in OB have not yet been revealed. Therefore, to investigate the alteration pattern of the transcription factors in OB, we used protein/DNA arrays. Mice orthotopic tracheal transplantation model was used in this studying. In this study, we explored the activity profiles of TFs in Protein/DNA array data of tracheal tissue in 14 and 28 day after transplanted. From a total of 345 screened TFs, we identified 42 TFs that showed associated with OB progression. Our data indicate that TFs may be potentially involved in the pathogenesis of OB, and can prevent, diagnose and treat OB after lung transplantation. In development of OB, some of the TFs may have ability to modulate the transcription of inflammatory proteins such cytokines, inflammatory enzymes and so on.