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Horenburg, C.

Publications and source records attributed to Horenburg, C..

2 recordsLinked to original sources

UFMylation regulates translational homeostasis and cell cycle progression

UFMylation, the posttranslational modification of proteins with ubiquitin fold modifier 1 (UFM1) is essential for metazoan life and is associated with multiple human diseases. Although UFMylation has been linked to endoplasmic reticulum (ER) stress, its biological functions and relevant cellular targets beyond the ER are obscure. Here, we show that UFMylation directly controls translation and cell division in a manner otherwise known for cellular homeostasis-sensing pathways such as mTOR. By combining cell cycle analyses, mass spectrometry and ribosome profiling we demonstrate that UFMylation is required for eIF4F translation initiation complex assembly and recruitment of the ribosome. Interference with UFMylation shuts down global translation, which is sensed by cyclin D1 and halts the cell cycle independently of integrated stress response signalling. Our findings establish UFMylation as a key regulator of translation and uncover a pathway that couples translational homeostasis to cell cycle progression via a ubiquitin-like modification.

cell biology↗

Conditional control of fluorescent protein degradation by an auxin-dependent nanobody

The conditional and reversible depletion of proteins by auxin-mediated degradation is a powerful tool to investigate protein functions in cells and whole organisms. However, its wider applications require fusing the auxin-inducible degron (AID) to individual target proteins. Thus, establishing the auxin system for multiple proteins can be challenging. Another approach for directed protein degradation are anti-GFP nanobodies, which can be applied to GFP stock collections that are readily available in different experimental models. Here, we combine the advantages of auxin and nanobody-based degradation technologies creating an AID-nanobody to degrade GFP-tagged proteins at different cellular structures in a conditional and reversible manner in human cells. We demonstrate efficient and reversible inactivation of the anaphase promoting complex/cyclosome (APC/C) and thus provide new means to study the functions of this essential ubiquitin E3 ligase. Further, we establish auxin degradation in a vertebrate model organism by employing AID-nanobodies in zebrafish.

cell biology↗