@article{YinBrocherFischeretal.2011,
  author    = {Yin, Jun and Brocher, Jan and Fischer, Utz and Winkler, Christoph},
  title     = {Mutant Prpf31 causes pre-mRNA splicing defects and rod photoreceptor cell degeneration in a zebrafish model for Retinitis pigmentosa},
  series = {Molecular neurodegeneration},
  volume    = {6},
  journal   = {Molecular neurodegeneration},
  number    = {56},
  doi       = {10.1186/1750-1326-6-56},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141090},
  pages     = {1-17},
  year      = {2011},
  abstract  = {Background: Retinitis pigmentosa (RP) is an inherited eye disease characterized by the progressive degeneration of rod photoreceptor cells. Mutations in pre-mRNA splicing factors including PRPF31 have been identified as cause for RP, raising the question how mutations in general factors lead to tissue specific defects. Results: We have recently shown that the zebrafish serves as an excellent model allowing the recapitulation of key events of RP. Here we use this model to investigate two pathogenic mutations in PRPF31, SP117 and AD5, causing the autosomal dominant form of RP. We show that SP117 leads to an unstable protein that is mislocalized to the rod cytoplasm. Importantly, its overexpression does not result in photoreceptor degeneration suggesting haploinsufficiency as the underlying cause in human RP patients carrying SP117. In contrast, overexpression of AD5 results in embryonic lethality, which can be rescued by wild-type Prpf31. Transgenic retina-specific expression of AD5 reveals that stable AD5 protein is initially localized in the nucleus but later found in the cytoplasm concurrent with progressing rod outer segment degeneration and apoptosis. Importantly, we show for the first time in vivo that retinal transcripts are wrongly spliced in adult transgenic retinas expressing AD5 and exhibiting increased apoptosis in rod photoreceptors. Conclusion: Our data suggest that distinct mutations in Prpf31 can lead to photoreceptor degeneration through different mechanisms, by haploinsufficiency or dominant-negative effects. Analyzing the AD5 effects in our animal model in vivo, our data imply that aberrant splicing of distinct retinal transcripts contributes to the observed retina defects.},
  language  = {en}
}
@article{ZhaoZhangBhuripanyoetal.2013,
  author    = {Zhao, Bo and Zhang, Keya and Bhuripanyo, Karan and Choi, Chan Hee J. and Villhauer, Eric B. and Li, Heng and Zheng, Ning and Kiyokawa, Hiroaki and Schindelin, Hermann and Yin, Jun},
  title     = {Profiling the Cross Reactivity of Ubiquitin with the Nedd8 Activating Enzyme by Phage Display},
  series = {PLoS ONE},
  volume    = {8},
  journal   = {PLoS ONE},
  number    = {e70312},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0070312},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128479},
  year      = {2013},
  abstract  = {The C-terminal peptides of ubiquitin (UB) and UB-like proteins (UBLs) play a key role in their recognition by the specific activating enzymes (E1s) to launch their transfer through the respective enzymatic cascades thus modifying cellular proteins. UB and Nedd8, a UBL regulating the activity of cullin-RING UB ligases, only differ by one residue at their C-termini; yet each has its specific E1 for the activation reaction. It has been reported recently that UAE can cross react with Nedd8 to enable its passage through the UB transfer cascade for protein neddylation. To elucidate differences in UB recognition by UAE and NAE, we carried out phage selection of a UB library with randomized C-terminal sequences based on the catalytic formation of UB similar to NAE thioester conjugates. Our results confirmed the previous finding that residue 72 of UB plays a "gate-keeping" role in E1 selectivity. We also found that diverse sequences flanking residue 72 at the UB C-terminus can be accommodated by NAE for activation. Furthermore heptameric peptides derived from the C-terminal sequences of UB variants selected for NAE activation can function as mimics of Nedd8 to form thioester conjugates with NAE and the downstream E2 enzyme Ubc12 in the Nedd8 transfer cascade. Once the peptides are charged onto the cascade enzymes, the full-length Nedd8 protein is effectively blocked from passing through the cascade for the critical modification of cullin. We have thus identified a new class of inhibitors of protein neddylation based on the profiles of the UB C-terminal sequences recognized by NAE.},
  language  = {en}
}