Spliceosomal small nuclear ribonucleoprotein particles (snRNPs) undergo a complex maturation pathway containing multiple steps in the nucleus and in the cytoplasm. snRNP biogenesis is strictly proofread and several quality control checkpoints are placed along the pathway. Here, we analyzed the fate of small nuclear RNAs (snRNAs) that are unable to acquire a ring of Sm proteins. We showed that snRNAs lacking the Sm ring are unstable and accumulate in P-bodies in an LSm1-dependent manner. We further provide evidence that defective snRNAs without the Sm binding site are uridylated at the 3' end and associate with DIS3L2 3'→5' exoribonuclease and LSm proteins. Finally, inhibition of 5'→3' exoribonuclease XRN1 increases association of ΔSm snRNAs with DIS3L2, which indicates competition and compensation between these two degradation enzymes. Together, we provide evidence that defective snRNAs without the Sm ring are uridylated and degraded by alternative pathways involving either DIS3L2 or LSm proteins and XRN1.

• MeSH
• exoribonukleasy metabolismus   MeSH
• HeLa buňky MeSH
• konformace nukleové kyseliny * MeSH
• lidé MeSH
• organely metabolismus   MeSH
• proteinový komplex SMN metabolismus   MeSH
• proteiny vázající RNA metabolismus   MeSH
• protoonkogenní proteiny metabolismus   MeSH
• RNA malá jaderná chemie   metabolismus   MeSH
• sekvence nukleotidů MeSH
• stabilita RNA MeSH
• transport RNA * MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DIS3L2 protein, human MeSH Prohlížeč
• exoribonukleasy MeSH
• GEMIN5 protein, human MeSH Prohlížeč
• LSM1 protein, human MeSH Prohlížeč
• proteinový komplex SMN MeSH
• proteiny vázající RNA MeSH
• protoonkogenní proteiny MeSH
• RNA malá jaderná MeSH

Spliceosomal snRNPs are complex particles that proceed through a fascinating maturation pathway. Several steps of this pathway are closely linked to nuclear non-membrane structures called Cajal bodies. In this review, I summarize the last 20 y of research in this field. I primarily focus on snRNP biogenesis, specifically on the steps that involve Cajal bodies. I also evaluate the contribution of the Cajal body in snRNP quality control and discuss the role of snRNPs in Cajal body formation.

• MeSH
• Cajalova tělíska metabolismus   MeSH
• genetická transkripce MeSH
• lidé MeSH
• posttranskripční úpravy RNA MeSH
• ribonukleoproteiny malé jaderné genetika   metabolismus   MeSH
• spliceozomy MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• ribonukleoproteiny malé jaderné MeSH