The growing pre-mRNA recruits actin and chromatin-modifying factors to transcriptionally active genes

Sjölinder, Mikael; Björk, Petra; Söderberg, Emilia; Sabri, Nafiseh; Farrants, Ann‐Kristin Östlund; Visa, Neus

doi:10.1101/gad.339405

Cited by 64 publications

(62 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These observations are in agreement with the results of our previous investigation in which we found the colocalization of SATB1 and F-actin in the transcriptionally active regions of the nuclei of CHO AA8 cells undergoing active cell death [24]. Many authors showed that actin may translocate into the cell nucleus to function as a transcriptional modulator of gene expression [1,3,[32][33][34][35][36]. We have previously demonstrated not only the translocation of F-actin into the nucleus, but also its involvement in chromatin remodeling during cell death [19][20][21][22][23].…”

supporting

confidence: 82%

The interactions between SATB1 and F-actin are important for mechanisms of active cell death

Grzanka

Kowalczyk²,

Izdebska³

et al. 2015

Folia Histochem Cytobiol.

View full text Add to dashboard Cite

Introduction. The direct involvement of nuclear actin filaments in gene transcription and remodeling of chromatin is still debatable. However, nuclear localization of F-actin and its interactions with other nuclear matrix proteins have been reported. The aim of the study was to estimate the interactions between nuclear F-actin and one of the matrix proteins, special AT-rich sequence-binding protein 1 (SATB1), during active cell death induced in vitro by geldanamycin (GA). Material and methods. The expression of SATB1 was modified by the transfection of non-aggressive breast cancer MCF-7 cells with siRNA against SATB1 or expression plasmid with cloned cDNA of SATB1. The amount and localization of F-actin were altered by changes of cofilin-1 (CFL1) expression in MCF-7 cells. The association between SATB1 and F-actin during GA-induced cell death was analyzed using confocal and transmission electron microscopy. Results. Our studies revealed the colocalization between nuclear F-actin and SATB1 protein, during GA-induced death of breast cancer MCF-7 cells. The colocalization was enhanced in cells with overexpressed SATB1 and cofilin-1. At the ultrastructural level the SATB1 and F-actin complexes were seen at the border of condensed and decondensed chromatin. The presence of SATB1/F-actin molecular complexes was confirmed by magnetic separation of F-actin and interacting proteins. Conclusion. We suggest that the molecular interactions between SATB1 and F-actin are necessary for active cell death to occur.

show abstract

supporting

confidence: 82%

The interactions between SATB1 and F-actin are important for mechanisms of active cell death

Grzanka

Kowalczyk²,

Izdebska³

et al. 2015

Folia Histochem Cytobiol.

View full text Add to dashboard Cite

show abstract

“…The presence of actin within the nucleus was first suggested in 1969 (20), but its role in the nucleus has been extremely controversial. One of the first demonstrations of a role for actin in the nucleus was as a collaborating factor in chromatin remodelling (21), an idea that has been increasingly confirmed and extended (22)(23)(24)(25).…”

Section: Introductionmentioning

confidence: 99%

Characterisation of a multimeric protein complex associated with ERp57 within the nucleus in paclitaxel-sensitive and -resistant epithelial ovarian cancer cells: The involvement of specific conformational states of β-actin

Cicchillitti¹,

Corte

Michele

et al. 2010

Int J Oncol

View full text Add to dashboard Cite

Abstract. Ovarian cancer is the second most frequently diagnosed malignancy of the reproductive system and is the leading cause of gynecological cancer mortality. Although the majority of advanced ovarian carcinomas initially respond successfully to taxane-based chemotherapy, resistance to chemotherapy remains the primary factor accounting for the low 5-year survival in this patient population. Recent data obtained by our group demonstrate that the disulphide isomerase ERp57 is strongly modulated in paclitaxel resistance suggesting that it may represent a chemoresistance biomarker in ovarian cancer. In the present study, we characterise a nuclear multimeric complex where ERp57 is associated with protein species involved in cell division and gene expression, as Nucleolin, Nucleophosmin, Vimentin, Aurora kinase C and ß-actin. In particular, we show that the occurrence of the interaction of nuclear ERp57 with ß-actin is associated with paclitaxel resistance and that specific actin conformations modulate this complex. We propose the involvement of the nuclear ERp57 complex in mechanisms associated with chromosome segregation in which specific conformational states of actin play a role in the pathway involved in paclitaxel resistance.

show abstract

“…The enzyme consists of 12 subunits named Rpb1 to Rpb12 in humans (Hampsey 1998). Evidence has shown that actin is a component of the Pol II PICs and acts as a platform for the recruitment of histone acetyltransferase (HAT) or histone deacetylase (HDAC) to the active transcription unit (Kukalev et al 2005;Sjolinder et al 2005;Obrdlik et al 2008). Moreover, actin could be affinity-purified with an Rpb4/Rpb7 column (Mitsuzawa et al 2005), raising the possibility that actin could interact with Pol II directly.…”

Section: Introductionmentioning

confidence: 99%

β-Actin regulates interleukin 6-induced p21 transcription by interacting with the Rpb5 and Rpb7 subunits of RNA polymerase II

Tian

Chen

et al. 2016

Animal Cells and Systems

View full text Add to dashboard Cite

In pre-initiation complexes, RNA helicase A interacts with β-actin and acts as a bridging factor linking nuclear actin with RNA polymerase II (Pol II). In addition, β-actin participates in Pol IIdependent transcription elongation by interacting with the positive transcription elongation factor Cdk9. However, many relationships between β-actin and Pol II remain to be identified. In an interleukin 6 (IL-6)-induced p21 expression model, we demonstrated that β-actin knockdown reduced p21 expression. Immunofluorescence analysis showed that the colocalization of β-actin and Pol II increased significantly in cells treated with IL-6. It is known that the Rpb5, Rpb6 and Rpb7 subunits are located at the surface of the enzyme. We next constructed recombinant pcDNA-HA-Rpb5, pcDNA-HA-Rpb6 and pcDNA-HA-Rpb7 plasmids and expressed the three polymerase II subunits in HepG2 cells. We found that β-actin could be immunoprecipitated with HA-Rpb5 and HA-Rpb7. A Glutathione-S-transferase pull-down assay revealed that β-actin was associated with Rpb5 and Rpb7 in vitro. Furthermore, overexpression of Rpb5 and Rpb7 in cells reduced p21 expression significantly, suggesting that Rpb5 and Rpb7 competitively interact with β-actin. This study shows that β-actin associates with Pol II subunits through direct proteinprotein interactions and provides fundamental insight into Pol II transcriptional regulation.

show abstract

The growing pre-mRNA recruits actin and chromatin-modifying factors to transcriptionally active genes

Cited by 64 publications

References 63 publications

The interactions between SATB1 and F-actin are important for mechanisms of active cell death

The interactions between SATB1 and F-actin are important for mechanisms of active cell death

Characterisation of a multimeric protein complex associated with ERp57 within the nucleus in paclitaxel-sensitive and -resistant epithelial ovarian cancer cells: The involvement of specific conformational states of β-actin

β-Actin regulates interleukin 6-induced p21 transcription by interacting with the Rpb5 and Rpb7 subunits of RNA polymerase II

Contact Info

Product

Resources

About