TY  - JOUR
A1  - Hickey, Scott F.
A1  - Sridhar, Malathy
A1  - Westermann, Alexander J.
A1  - Qin, Qian
A1  - Vijayendra, Pooja
A1  - Liou, Geoffrey
A1  - Hammond, Ming C.
T1  - Transgene regulation in plants by alternative splicing of a suicide exon
JF  - Nucleic Acids Research
N2  - Compared to transcriptional activation, other mechanisms of gene regulation have not been widely exploited for the control of transgenes. One barrier to the general use and application of alternative splicing is that splicing-regulated transgenes have not been shown to be reliably and simply designed. Here, we demonstrate that a cassette bearing a suicide exon can be inserted into a variety of open reading frames (ORFs), generating transgenes whose expression is activated by exon skipping in response to a specific protein inducer. The surprisingly minimal sequence requirements for the maintenance of splicing fidelity and regulation indicate that this splicing cassette can be used to regulate any ORF containing one of the amino acids Glu, Gln or Lys. Furthermore, a single copy of the splicing cassette was optimized by rational design to confer robust gene activation with no background expression in plants. Thus, conditional splicing has the potential to be generally useful for transgene regulation.
KW  - kingdom
KW  - pre-messenger RNA
KW  - gene expression
KW  - elements
KW  - decay
KW  - arabidopsis
KW  - eukaryotes
KW  - mechanisms
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134724
VL  - 40
IS  - 10
ER  - 
TY  - JOUR
A1  - Schulte, Leon N.
A1  - Westermann, Alexander J.
A1  - Vogel, Jörg
T1  - Differential activation and functional specialization of miR-146 and miR-155 in innate immune sensing
N2  - Many microRNAs (miRNAs) are co-regulated during the same physiological process but the underlying cellular logic is often little understood. The conserved, immunomodulatory miRNAs miR-146 and miR-155, for instance, are co-induced in many cell types in response to microbial lipopolysaccharide (LPS) to feedback-repress LPS signalling through Toll-like receptor TLR4. Here, we report that these seemingly co-induced regulatory RNAs dramatically differ in their induction behaviour under various stimuli strengths and act non-redundantly through functional specialization; although miR-146 expression saturates at sub-inflammatory doses of LPS that do not trigger the messengers of inflammation markers, miR-155 remains tightly associated with the pro-inflammatory transcriptional programmes. Consequently, we found that both miRNAs control distinct mRNA target profiles; although miR-146 targets the messengers of LPS signal transduction components and thus downregulates cellular LPS sensitivity, miR-155 targets the mRNAs of genes pervasively involved in pro-inflammatory transcriptional programmes. Thus, miR-155 acts as a broad limiter of pro-inflammatory gene expression once the miR-146 dependent barrier to LPS triggered inflammation has been breached. Importantly, we also report alternative miR-155 activation by the sensing of bacterial peptidoglycan through cytoplasmic NOD-like receptor, NOD2. We predict that dosedependent responses to environmental stimuli may involve functional specialization of seemingly coinduced miRNAs in other cellular circuitries as well.
KW  - Medizin
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76365
ET  - Advance Access
ER  -