TY  - JOUR
A1  - Waldholm, Johan
A1  - Wang, Zhi
A1  - Brodin, David
A1  - Tyagi, Anu
A1  - Yu, Simei
A1  - Theopold, Ulrich
A1  - Östlund Farrants, Ann Kristin
A1  - Visa, Neus
T1  - SWI/SNF regulates the alternative processing of a specific subset of pre-mRNAs in \(Drosophila\) \(melanogaster\)
JF  - BMC Molecular Biology
N2  - Background: 

The SWI/SNF chromatin remodeling factors have the ability to remodel nucleosomes and play essential roles in key developmental processes. SWI/SNF complexes contain one subunit with ATPase activity, which in Drosophila melanogaster is called Brahma (Brm). The regulatory activities of SWI/SNF have been attributed to its influence on chromatin structure and transcription regulation, but recent observations have revealed that the levels of Brm affect the relative abundances of transcripts that are formed by alternative splicing and/or polyadenylation of the same pre-mRNA. 

Results: 

We have investigated whether the function of Brm in pre-mRNA processing in Drosophila melanogaster is mediated by Brm alone or by the SWI/SNF complex. We have analyzed the effects of depleting individual SWI/SNF subunits on pre-mRNA processing throughout the genome, and we have identified a subset of transcripts that are affected by depletion of the SWI/SNF core subunits Brm, Snr1 or Mor. The fact that depletion of different subunits targets a subset of common transcripts suggests that the SWI/SNF complex is responsible for the effects observed on pre-mRNA processing when knocking down Brm. We have also depleted Brm in larvae and we have shown that the levels of SWI/SNF affect the pre-mRNA processing outcome in vivo. 

Conclusions: 

We have shown that SWI/SNF can modulate alternative pre-mRNA processing, not only in cultured cells but also in vivo. The effect is restricted to and specific for a subset of transcripts. Our results provide novel insights into the mechanisms by which SWI/SNF regulates transcript diversity and proteomic diversity in higher eukaryotes.
KW  - Chromatin-remodeling complexes
KW  - In-vivo
KW  - Genes
KW  - Distinct
KW  - Brahma
KW  - Transcription
KW  - Trithorax
KW  - Subunit
KW  - Exons
KW  - BRM
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142613
VL  - 12
IS  - 46
ER  - 
TY  - JOUR
A1  - Ma, Eric Yue
A1  - Calvo, M. Reyes
A1  - Wang, Jing
A1  - Lian, Biao
A1  - Mühlbauer, Mathias
A1  - Brüne, Christoph
A1  - Cui, Yong-Tao
A1  - Lai, Keji
A1  - Kundhikanjana, Worasom
A1  - Yang, Yongliang
A1  - Baenninger, Matthias
A1  - König, Markus
A1  - Ames, Christopher
A1  - Buhmann, Hartmut
A1  - Leubner, Philipp
A1  - Molenkamp, Laurens W.
A1  - Zhang, Shou-Cheng
A1  - Goldhaber-Gordon, David
A1  - Kelly, Michael A.
A1  - Shen, Zhi-Xun
T1  - Unexpected edge conduction in mercury telluride quantum wells under broken time-reversal symmetry
JF  - Nature Communications
N2  - The realization of quantum spin Hall effect in HgTe quantum wells is considered a milestone in the discovery of topological insulators. Quantum spin Hall states are predicted to allow current flow at the edges of an insulating bulk, as demonstrated in various experiments. A key prediction yet to be experimentally verified is the breakdown of the edge conduction under broken time-reversal symmetry. Here we first establish a systematic framework for the magnetic field dependence of electrostatically gated quantum spin Hall devices. We then study edge conduction of an inverted quantum well device under broken time-reversal symmetry using microwave impedance microscopy, and compare our findings to a noninverted device. At zero magnetic field, only the inverted device shows clear edge conduction in its local conductivity profile, consistent with theory. Surprisingly, the edge conduction persists up to 9 T with little change. This indicates physics beyond simple quantum spin Hall model, including material-specific properties and possibly many-body effects.
KW  - topological insulators
KW  - surface states
KW  - HgTe
KW  - Hg1-xCdxTe
KW  - vacancies
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143185
VL  - 6
IS  - 7252
ER  -