Asunto(s)
Genes de Plantas/genética , Familia de Multigenes/genética , Péptido Hidrolasas/genética , Proteínas de Plantas/genética , Plantas/genética , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/genética , Péptido Hidrolasas/clasificación , Péptido Hidrolasas/metabolismo , Proteínas de Plantas/clasificación , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/clasificación , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Terminología como AsuntoRESUMEN
Mechanisms underlying anteroposterior body axis differences during adult tissue maintenance and regeneration are poorly understood. Here, we identify that post-translational modifications through the SUMO (Small Ubiquitin-like Modifier) machinery are evolutionarily conserved in the Lophotrocozoan Schmidtea mediterranea. Disruption of SUMOylation in adult animals by RNA-interference of the only SUMO E2 conjugating enzyme Ubc9 leads to a systemic increase in DNA damage and a remarkable regional defect characterized by increased cell death and loss of the posterior half of the body. We identified that Ubc9 is mainly expressed in planarian stem cells (neoblasts) but it is also transcribed in differentiated cells including neurons. Regeneration in Ubc9(RNAi) animals is impaired and associated with low neoblast proliferation. We present evidence indicating that Ubc9-induced regional cell death is preceded by alterations in transcription and spatial expression of repressors and activators of the Hedgehog signaling pathway. Our results demonstrate that SUMOylation acts as a regional-specific cue to regulate cell fate during tissue renewal and regeneration.
Asunto(s)
Proliferación Celular , Proteínas Hedgehog/metabolismo , Proteínas del Helminto/metabolismo , Planarias/metabolismo , Transducción de Señal , Células Madre/metabolismo , Secuencia de Aminoácidos , Animales , Muerte Celular , Proteínas Hedgehog/genética , Proteínas del Helminto/clasificación , Proteínas del Helminto/genética , Filogenia , Planarias/citología , Planarias/genética , Interferencia de ARN , Homología de Secuencia de Aminoácido , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/clasificación , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/genética , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Células Madre/citología , Sumoilación , Enzimas Ubiquitina-Conjugadoras/clasificación , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismoRESUMEN
Small ubiquitin-like modifiers (SUMOs) are essential for the regulation of several cellular processes and are potential therapeutic targets owing to their involvement in diseases such as cancer and Alzheimer disease. In the past decade, we have witnessed a rapid expansion of proteomic approaches for identifying sumoylated proteins, with recent advances in detecting site-specific sumoylation. In this Analysis, we combined all human SUMO proteomics data currently available into one cohesive database. We provide proteomic evidence for sumoylation of 3,617 proteins at 7,327 sumoylation sites, and insight into SUMO group modification by clustering the sumoylated proteins into functional networks. The data support sumoylation being a frequent protein modification (on par with other major protein modifications) with multiple nuclear functions, including in transcription, mRNA processing, DNA replication and the DNA-damage response.
Asunto(s)
Bases de Datos de Proteínas , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/clasificación , Humanos , Procesamiento Proteico-Postraduccional , Proteínas/química , Proteínas/metabolismo , Proteómica , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/fisiología , SumoilaciónRESUMEN
In the last decade, SUMOylation has emerged as an essential post-translational modification in eukaryotes. In plants, the biological role of SUMO (small ubiquitin-related modifier) has been studied through genetic approaches that together with recent biochemical studies suggest that the plant SUMOylation system has a high degree of complexity. The present review summarizes our current knowledge on the SUMOylation system in Arabidopsis, focusing on the mechanistic properties of the machinery components identified.
Asunto(s)
Proteínas de Arabidopsis/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/clasificación , Proteínas de Arabidopsis/genética , Datos de Secuencia Molecular , Filogenia , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/clasificación , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/genéticaRESUMEN
The small ubiquitin-like modifier (SUMO) is covalently attached to lysine residues in target proteins and in doing so changes the properties of the modified protein. Here we examine the role of SUMO modification in transcriptional regulation. SUMO addition to components of the transcriptional apparatus does not have a common consequence as it can both activate and repress transcription. In most cases, however, SUMO modification of transcription factors leads to repression and various models to explain this, ranging from retention in nuclear bodies to recruitment of histone deacetylases are discussed.
