Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The control of ribosome biogenesis is a critical cellular nodal point, which ensures that protein synthesis is coordinated with cell growth and proliferation. Prior to their cytoplasmic assembly the 40S and 60S ribosomal subunits pass through the nucleolus and the nucleoplasm via a maturation pathway that involves a set of non-coding RNAs and non-ribosomal regulatory trans-acting factors. In mammalian cells the inventory of the required protein components is still fragmentary and it is largely unclear what drives the subcellular transitions and the exchange of protein components along the maturation pathway. However, recent data indicate that the dynamic post-translational modification by the ubiquitin-like SUMO modifier is critically involved in these processes. In particular, removal of SUMO from trans-acting factors by the SUMO-specific isopeptidase SENP3 is instrumental in the 60S maturation pathway in mammals. In an attempt to pinpoint the relevant targets of SENP3 we identified a novel SENP3-associated protein complex comprised of PELP1, TEX10 and WDR18. We demonstrated that this complex is involved in the nucleolar steps of 28S rRNA maturation and the subsequent nucleoplasmic transit of the 60S ribosomal subunit. Importantly, we found that PELP1 is a SENP3-sensitive target of SUMO and observed that lack of SENP3-mediated desumoylation prevents the nucleolar partitioning of the PELP1-TEX10-WDR18 complex. SUMO-dependent subnuclear trafficking may thus assist in coordinating the rate of ribosome formation. Here we propose that sumoylation of PELP1 serves as a quality control mechanism that restricts pre-mature loading of the PELP1-WDR18-TEX10 complex to 60S particles thereby limiting ribosome maturation. We further hypothesize that the PELP1-associated AAA-ATPase MDN1 may be part of this surveillance pathway.
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PMID:SUMO routes ribosome maturation. 2206 70

Biogenesis of translation-competent 80S ribosomes is a multi-step process requiring the sequential action of non-ribosomal trans-acting factors. We previously identified the human PELP1-TEX10-WDR18 complex and the associated SUMO isopeptidase SENP3 as regulators of 60S maturation. We provided evidence that deconjugating SUMO from PELP1 by SENP3 is instrumental for proper ribosome biogenesis. Here we show that SUMO conjugation/deconjugation of PELP1 controls its dynamic association with the AAA ATPase MDN1, a key factor of pre-60S remodeling. We demonstrate that modification of PELP1 promotes the recruitment of MDN1 to pre-60S particles, while deSUMOylation is needed to release both MDN1 and PELP1 from pre-ribosomes. Inactivation of SENP3 traps MDN1 at pre-60S particles and prevents critical remodeling events, ultimately generating aberrant pre-60S complexes. We define MDN1 as a SUMO-targeted AAA ATPase, and we propose that a controlled SUMO cycle on PELP1 serves as regulatory point for mammalian 60S maturation through ordered recruitment and release of MDN1.
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PMID:The AAA ATPase MDN1 Acts as a SUMO-Targeted Regulator in Mammalian Pre-ribosome Remodeling. 2781 92