TY  - JOUR
AB  - Mammalian cells can be reprogrammed into induced pluripotent stem cells (iPSCs), a valuable tool for in vitro disease modeling and regenerative medicine. These applications demand for iPSCs devoid of reprogramming factor transgenes, but current procedures for the derivation of transgene-free iPSCs are inefficient and cumbersome. Here, we describe a new approach for the simple derivation of transgene-free iPSCs by the sequential use of two DNA recombinases, C31 Integrase and Cre, to control the genomic insertion and excision of a single, non-viral reprogramming vector. We show that such transgene-free iPSCs exhibit gene expression profiles and pluripotent developmental potential comparable to genuine, blastocyst-derived embryonic stem cells. As shown by a reporter iPSC line for the differentiation into midbrain dopaminergic neurons, the dual recombinase approach offers a simple and efficient way to derive transgene-free iPSCs for studying disease mechanisms and cell replacement therapies.
AU  - Pertek, A.
AU  - Meier, F.
AU  - Irmler, M.
AU  - Beckers, J.
AU  - Skylaki, S.
AU  - Endele, M.
AU  - Wurst, W.
AU  - Prakash, N.
AU  - Kühn, R.
C1  - 30917
C2  - 34022
CY  - Totowa
SP  - 697-713
TI  - Simple derivation of transgene-free iPS cells by a dual recombinase approach.
JO  - Mol. Biotechnol.
VL  - 56
IS  - 8
PB  - Humana Press Inc
PY  - 2014
SN  - 1073-6085
ER  - 

TY  - JOUR
AB  - In recent years RNA interference (RNAi) has become a useful genetic tool to downregulate candidate disease genes for which pharmaceutical inhibitors are not available. In combination with viral vectors to trigger RNAi in the mammalian body, it allows the localized and specific manipulation of the expression of single or multiple genes in vivo. The MAP kinases ERK1 and ERK2 are involved in the transduction of extracellular signals to nuclear effectors. A role for ERKs has been proposed in the adult brain in mediating neuronal functions, as for fear learning in the lateral amygdala. To study the role of ERK in anxiety disorders characterized by disturbed fear learning processes we developed Erk-specific RNAi tools and tested the efficacy of a viral Erk2 vector in the adult mouse brain. We found shRNAs that showed silencing of either both ERK1/2 or only ERK2. In particular, our analysis showed that an Erk2-specific shRNA reduced the activity of this gene at comparable efficiency both in vitro and in vivo. This reagent provides a useful tool to study the role of ERK2, for which small molecule inhibitors are not available, in the development of anxiety and other psychiatric disorders.
AU  - di Benedetto, B.
AU  - Wefers, B.
AU  - Wurst, W.
AU  - Kühn, R.
C1  - 2876
C2  - 25893
SP  - 263-269
TI  - Local Knockdown of ERK2 in the Adult Mouse Brain Via Adeno-Associated Virus-Mediated RNA Interference.
JO  - Mol. Biotechnol.
VL  - 41
IS  - 3
PB  - Humana Press Inc.
PY  - 2009
SN  - 1073-6085
ER  - 

TY  - JOUR
AB  - Mitochondria are crucial for normal cell metabolism and maintenance. Mitochondrial dysfunction has been implicated in a spectrum of human diseases, ranging from rare monogenic to common multifactorial disorders. Important for the understanding of organelle function is the assignment of its constituents, and although over 1,500 proteins are predicted to be involved in mammalian mitochondrial function, so far only about 900 are assigned to mitochondria with reasonable certainty. Continuing efforts are being taken to obtain a complete inventory of the mitochondrial proteome by single protein studies and high-throughput approaches. To be of best value for the scientific community this data needs to be structured, explored, and customized. For this purpose, the MitoP2 database (http://www.mitop2.de) was established and is maintained in order to incorporate such data. The central database contains manually evaluated yeast, mouse, and human reference proteins, which show convincing evidence of a mitochondrial location. In addition, entries from genome-wide approaches that suggest protein localization are integrated and serve to compile a combined score for each candidate, which provides a best estimate of mitochondrial localization. Furthermore, it integrates information on the orthology between species, including Saccharomyces cerevisiae, mouse, human, Arabidopsis thaliana, and Neurospora crassa, thus mutually enhancing evidence across species. In contrast to other known databases, MitoP2 takes into account the reliability by which the protein is estimated as being mitochondrially located, as described herein. Multiple search functions, as well as information on disease causing genes and available mouse models, makes MitoP2 a valuable tool for the genetic investigation of human mitochondrial pathology.
AU  - Elstner, M.
AU  - Andreoli, C.*
AU  - Ahting, U.
AU  - Tetko, I.V.
AU  - Klopstock, T.*
AU  - Meitinger, T.
AU  - Prokisch, H.
C1  - 1937
C2  - 25910
SP  - 306-315
TI  - MitoP2: An integrative tool for the analysis of the mitochondrial proteome.
JO  - Mol. Biotechnol.
VL  - 40
IS  - 3
PB  - Humana Press Inc.
PY  - 2008
SN  - 1073-6085
ER  -