TY  - JOUR
A1  - Baluapuri, Apoorva
A1  - Hofstetter, Julia
A1  - Dudvarski Stankovic, Nevenka
A1  - Endres, Theresa
A1  - Bhandare, Pranjali
A1  - Vos, Seychelle Monique
A1  - Adhikari, Bikash
A1  - Schwarz, Jessica Denise
A1  - Narain, Ashwin
A1  - Vogt, Markus
A1  - Wang, Shuang-Yan
A1  - Düster, Robert
A1  - Jung, Lisa Anna
A1  - Vanselow, Jens Thorsten
A1  - Wiegering, Armin
A1  - Geyer, Matthias
A1  - Maric, Hans Michael
A1  - Gallant, Peter
A1  - Walz, Susanne
A1  - Schlosser, Andreas
A1  - Cramer, Patrick
A1  - Eilers, Martin
A1  - Wolf, Elmar
T1  - MYC Recruits SPT5 to RNA Polymerase II to Promote Processive Transcription Elongation
JF  - Molecular Cell
N2  - The MYC oncoprotein binds to promoter-proximal regions of virtually all transcribed genes and enhances RNA polymerase II (Pol II) function, but its precise mode of action is poorly understood. Using mass spectrometry of both MYC and Pol II complexes, we show here that MYC controls the assembly of Pol II with a small set of transcription elongation factors that includes SPT5, a subunit of the elongation factor DSIF. MYC directly binds SPT5, recruits SPT5 to promoters, and enables the CDK7-dependent transfer of SPT5 onto Pol II. Consistent with known functions of SPT5, MYC is required for fast and processive transcription elongation. Intriguingly, the high levels of MYC that are expressed in tumors sequester SPT5 into non-functional complexes, thereby decreasing the expression of growth-suppressive genes. Altogether, these results argue that MYC controls the productive assembly of processive Pol II elongation complexes and provide insight into how oncogenic levels of MYC permit uncontrolled cellular growth.
KW  - MYC
KW  - SPT5
KW  - SUPT5H
KW  - SPT6
KW  - RNA polymerase II
KW  - transcription
KW  - elongation rate
KW  - processivity
KW  - directionality
KW  - tumorigenesis
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-221438
VL  - 74
ER  - 
TY  - JOUR
A1  - Otto, Christoph
A1  - Kastner, Carolin
A1  - Schmidt, Stefanie
A1  - Uttinger, Konstantin
A1  - Baluapuri, Apoorva
A1  - Denk, Sarah
A1  - Rosenfeldt, Mathias T.
A1  - Rosenwald, Andreas
A1  - Roehrig, Florian
A1  - Ade, Carsten P.
A1  - Schuelein-Voelk, Christina
A1  - Diefenbacher, Markus E.
A1  - Germer, Christoph-Thomas
A1  - Wolf, Elmar
A1  - Eilers, Martin
A1  - Wiegering, Armin
T1  - RNA polymerase I inhibition induces terminal differentiation, growth arrest, and vulnerability to senolytics in colorectal cancer cells
JF  - Molecular Oncology
N2  - Ribosomal biogenesis and protein synthesis are deregulated in most cancers, suggesting that interfering with translation machinery may hold significant therapeutic potential. Here, we show that loss of the tumor suppressor adenomatous polyposis coli (APC), which constitutes the initiating event in the adenoma carcinoma sequence for colorectal cancer (CRC), induces the expression of RNA polymerase I (RNAPOL1) transcription machinery, and subsequently upregulates ribosomal DNA (rDNA) transcription. Targeting RNAPOL1 with a specific inhibitor, CX5461, disrupts nucleolar integrity, and induces a disbalance of ribosomal proteins. Surprisingly, CX5461-induced growth arrest is irreversible and exhibits features of senescence and terminal differentiation. Mechanistically, CX5461 promotes differentiation in an MYC-interacting zinc-finger protein 1 (MIZ1)- and retinoblastoma protein (Rb)-dependent manner. In addition, the inhibition of RNAPOL1 renders CRC cells vulnerable towards senolytic agents. We validated this therapeutic effect of CX5461 in murine- and patient-derived organoids, and in a xenograft mouse model. These results show that targeting ribosomal biogenesis together with targeting the consecutive, senescent phenotype using approved drugs is a new therapeutic approach, which can rapidly be transferred from bench to bedside.
KW  - CRC
KW  - CX5461
KW  - MIZ1
KW  - MYC
KW  - ribosome
KW  - RNAPOL1
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312806
VL  - 16
IS  - 15
ER  -