Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription
The Mediator complex is a greater than 1-megadalton complex, composed of about 30 subunits and found in most eukaryotes, whose main role is to transmit signals from DNA-bound transcription factors to RNA Polymerase II. The proteasome is emerging as an important regulator of transcription during both...
Guardado en:
| Autor principal: | |
|---|---|
| Publicado: |
2012
|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00320889_v160_n3_p1662_Inigo http://hdl.handle.net/20.500.12110/paper_00320889_v160_n3_p1662_Inigo |
| Aporte de: |
| id |
paper:paper_00320889_v160_n3_p1662_Inigo |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_00320889_v160_n3_p1662_Inigo2023-06-08T15:00:01Z Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription Cerdán, Pablo Diego Arabidopsis protein FT protein, Arabidopsis nuclear protein PFT1 protein, Arabidopsis proteasome ubiquitin protein ligase amino acid sequence Arabidopsis article chemistry flower gene expression regulation gene silencing genetic transcription genetics metabolism molecular genetics mutation physiology protein binding protein degradation protein stability protein tertiary structure Amino Acid Sequence Arabidopsis Arabidopsis Proteins Flowers Gene Expression Regulation, Plant Gene Knockdown Techniques Molecular Sequence Data Mutation Nuclear Proteins Proteasome Endopeptidase Complex Protein Binding Protein Stability Protein Structure, Tertiary Proteolysis Transcription, Genetic Ubiquitin-Protein Ligases Arabidopsis Arabidopsis thaliana Eukaryota Saccharomyces cerevisiae The Mediator complex is a greater than 1-megadalton complex, composed of about 30 subunits and found in most eukaryotes, whose main role is to transmit signals from DNA-bound transcription factors to RNA Polymerase II. The proteasome is emerging as an important regulator of transcription during both initiation and elongation. It is increasing the number of cases where the proteolysis of transcriptional activators by the proteasome activates their function. This counterintuitive phenomenon was called "activation by destruction." Here, we show that, in Arabidopsis (Arabidopsis thaliana), PHYTOCHROME AND FLOWERING TIME1 (PFT1), the MEDIATOR25 (MED25) subunit of the plant Mediator complex, is degraded by the proteasome and that proteasome-mediated PFT1 turnover is coupled to its role in stimulating the transcription of FLOWERING LOCUS T, the plant florigen, which is involved in the process of flowering induction. We further identify two novel RING-H2 proteins that target PFT1 for degradation. We show that MED25-BINDING RING-H2 PROTEIN1 (MBR1) and MBR2 bind to PFT1 in yeast (Saccharomyces cerevisiae) and in vitro, and they promote PFT1 degradation in vivo, in a RING-H2- dependent way, typical of E3 ubiquitin ligases. We further show that both MBR1 and MBR2 also promote flowering by PFT1- dependent and -independent mechanisms. Our findings extend the phenomenon of activation by destruction to a Mediator subunit, adding a new mechanism by which Mediator subunits may regulate downstream genes in specific pathways. Furthermore, we show that two novel RING-H2 proteins are involved in the destruction of PFT1, adding new players to this process in plants. © 2012 American Society of Plant Biologists. Fil:Cerdán, P.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2012 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00320889_v160_n3_p1662_Inigo http://hdl.handle.net/20.500.12110/paper_00320889_v160_n3_p1662_Inigo |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Arabidopsis protein FT protein, Arabidopsis nuclear protein PFT1 protein, Arabidopsis proteasome ubiquitin protein ligase amino acid sequence Arabidopsis article chemistry flower gene expression regulation gene silencing genetic transcription genetics metabolism molecular genetics mutation physiology protein binding protein degradation protein stability protein tertiary structure Amino Acid Sequence Arabidopsis Arabidopsis Proteins Flowers Gene Expression Regulation, Plant Gene Knockdown Techniques Molecular Sequence Data Mutation Nuclear Proteins Proteasome Endopeptidase Complex Protein Binding Protein Stability Protein Structure, Tertiary Proteolysis Transcription, Genetic Ubiquitin-Protein Ligases Arabidopsis Arabidopsis thaliana Eukaryota Saccharomyces cerevisiae |
| spellingShingle |
Arabidopsis protein FT protein, Arabidopsis nuclear protein PFT1 protein, Arabidopsis proteasome ubiquitin protein ligase amino acid sequence Arabidopsis article chemistry flower gene expression regulation gene silencing genetic transcription genetics metabolism molecular genetics mutation physiology protein binding protein degradation protein stability protein tertiary structure Amino Acid Sequence Arabidopsis Arabidopsis Proteins Flowers Gene Expression Regulation, Plant Gene Knockdown Techniques Molecular Sequence Data Mutation Nuclear Proteins Proteasome Endopeptidase Complex Protein Binding Protein Stability Protein Structure, Tertiary Proteolysis Transcription, Genetic Ubiquitin-Protein Ligases Arabidopsis Arabidopsis thaliana Eukaryota Saccharomyces cerevisiae Cerdán, Pablo Diego Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| topic_facet |
Arabidopsis protein FT protein, Arabidopsis nuclear protein PFT1 protein, Arabidopsis proteasome ubiquitin protein ligase amino acid sequence Arabidopsis article chemistry flower gene expression regulation gene silencing genetic transcription genetics metabolism molecular genetics mutation physiology protein binding protein degradation protein stability protein tertiary structure Amino Acid Sequence Arabidopsis Arabidopsis Proteins Flowers Gene Expression Regulation, Plant Gene Knockdown Techniques Molecular Sequence Data Mutation Nuclear Proteins Proteasome Endopeptidase Complex Protein Binding Protein Stability Protein Structure, Tertiary Proteolysis Transcription, Genetic Ubiquitin-Protein Ligases Arabidopsis Arabidopsis thaliana Eukaryota Saccharomyces cerevisiae |
| description |
The Mediator complex is a greater than 1-megadalton complex, composed of about 30 subunits and found in most eukaryotes, whose main role is to transmit signals from DNA-bound transcription factors to RNA Polymerase II. The proteasome is emerging as an important regulator of transcription during both initiation and elongation. It is increasing the number of cases where the proteolysis of transcriptional activators by the proteasome activates their function. This counterintuitive phenomenon was called "activation by destruction." Here, we show that, in Arabidopsis (Arabidopsis thaliana), PHYTOCHROME AND FLOWERING TIME1 (PFT1), the MEDIATOR25 (MED25) subunit of the plant Mediator complex, is degraded by the proteasome and that proteasome-mediated PFT1 turnover is coupled to its role in stimulating the transcription of FLOWERING LOCUS T, the plant florigen, which is involved in the process of flowering induction. We further identify two novel RING-H2 proteins that target PFT1 for degradation. We show that MED25-BINDING RING-H2 PROTEIN1 (MBR1) and MBR2 bind to PFT1 in yeast (Saccharomyces cerevisiae) and in vitro, and they promote PFT1 degradation in vivo, in a RING-H2- dependent way, typical of E3 ubiquitin ligases. We further show that both MBR1 and MBR2 also promote flowering by PFT1- dependent and -independent mechanisms. Our findings extend the phenomenon of activation by destruction to a Mediator subunit, adding a new mechanism by which Mediator subunits may regulate downstream genes in specific pathways. Furthermore, we show that two novel RING-H2 proteins are involved in the destruction of PFT1, adding new players to this process in plants. © 2012 American Society of Plant Biologists. |
| author |
Cerdán, Pablo Diego |
| author_facet |
Cerdán, Pablo Diego |
| author_sort |
Cerdán, Pablo Diego |
| title |
Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| title_short |
Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| title_full |
Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| title_fullStr |
Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| title_full_unstemmed |
Proteasome-mediated turnover of arabidopsis MED25 is coupled to the activation of FLOWERING LOCUS T transcription |
| title_sort |
proteasome-mediated turnover of arabidopsis med25 is coupled to the activation of flowering locus t transcription |
| publishDate |
2012 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00320889_v160_n3_p1662_Inigo http://hdl.handle.net/20.500.12110/paper_00320889_v160_n3_p1662_Inigo |
| work_keys_str_mv |
AT cerdanpablodiego proteasomemediatedturnoverofarabidopsismed25iscoupledtotheactivationoffloweringlocusttranscription |
| _version_ |
1768545544895987712 |