TY  - JOUR
A1  - Fischer, Annette
A1  - Harrison, Kelly S
A1  - Ramirez, Yesid
A1  - Auer, Daniela
A1  - Chowdhury, Suvagata Roy
A1  - Prusty, Bhupesh K
A1  - Sauer, Florian
A1  - Dimond, Zoe
A1  - Kisker, Caroline
A1  - Hefty, P Scott
A1  - Rudel, Thomas
T1  - Chlamydia trachomatis-containing vacuole serves as deubiquitination platform to stabilize Mcl-1 and to interfere with host defense
JF  - eLife
N2  - Obligate intracellular Chlamydia trachomatis replicate in a membrane-bound vacuole called inclusion, which serves as a signaling interface with the host cell. Here, we show that the chlamydial deubiquitinating enzyme (Cdu) 1 localizes in the inclusion membrane and faces the cytosol with the active deubiquitinating enzyme domain. The structure of this domain revealed high similarity to mammalian deubiquitinases with a unique α-helix close to the substrate-binding pocket. We identified the apoptosis regulator Mcl-1 as a target that interacts with Cdu1 and is stabilized by deubiquitination at the chlamydial inclusion. A chlamydial transposon insertion mutant in the Cdu1-encoding gene exhibited increased Mcl-1 and inclusion ubiquitination and reduced Mcl-1 stabilization. Additionally, inactivation of Cdu1 led to increased sensitivity of C. trachomatis for IFNγ and impaired infection in mice. Thus, the chlamydial inclusion serves as an enriched site for a deubiquitinating activity exerting a function in selective stabilization of host proteins and protection from host defense.
KW  - cell-autonomous defense
KW  - Chlamydia trachomatis
KW  - deubiquitinase
KW  - Mcl-1
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171073
VL  - 6
IS  - e21465
ER  - 
TY  - JOUR
A1  - Lorenzin, Francesca
A1  - Benary, Uwe
A1  - Baluapuri, Apoorva
A1  - Walz, Susanne
A1  - Jung, Lisa Anna
A1  - von Eyss, Björn
A1  - Kisker, Caroline
A1  - Wolf, Jana
A1  - Eilers, Martin
A1  - Wolf, Elmar
T1  - Different promoter affinities account for specificity in MYC-dependent gene regulation
JF  - eLife
N2  - Enhanced expression of the MYC transcription factor is observed in the majority of tumors. Two seemingly conflicting models have been proposed for its function: one proposes that MYC enhances expression of all genes, while the other model suggests gene-specific regulation. Here, we have explored the hypothesis that specific gene expression profiles arise since promoters differ in affinity for MYC and high-affinity promoters are fully occupied by physiological levels of MYC. We determined cellular MYC levels and used RNA- and ChIP-sequencing to correlate promoter occupancy with gene expression at different concentrations of MYC. Mathematical modeling showed that binding affinities for interactions of MYC with DNA and with core promoter-bound factors, such as WDR5, are sufficient to explain promoter occupancies observed in vivo. Importantly, promoter affinity stratifies different biological processes that are regulated by MYC, explaining why tumor-specific MYC levels induce specific gene expression programs and alter defined biological properties of cells.
KW  - MYC
KW  - promoter affinity
KW  - human
KW  - mathematical modeling
KW  - mouse
KW  - ChIP-sequencing
KW  - MIZ1
KW  - cancer biology
KW  - cell biology
KW  - WDR5
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-162913
VL  - 5
ER  -