In vivo kinetics of U4/U6.U5 tri-snRNP formation in Cajal bodies

0355300 - ÚMG 2011 RIV US eng J - Journal Article
Novotný, Ivan - Blažíková, Michaela - Staněk, David - Heřman, P. - Malínský, Jan
In vivo kinetics of U4/U6.U5 tri-snRNP formation in Cajal bodies.
Molecular Biology of the Cell. Roč. 22, č. 4 (2011), s. 513-523. ISSN 1059-1524. E-ISSN 1939-4586
R&D Projects: GA ČR GA204/07/0133; GA AV ČR KAN200520801
Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50390512; CEZ:AV0Z50390703
Keywords : small nuclear ribonucleoprotein * body components * dynamics
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 4.942, year: 2011

The U4/U6.U5 tri-snRNP is an essential pre-mRNA splicing factor, which is assembled in a step-wise manner before each round of splicing. It was previously shown that the tri-snRNP is formed in Cajal bodies (CBs) but little is known about the dynamics of this process. Here we created a mathematical model of tri-snRNP assembly in CBs and used it to fit kinetics of individual snRNPs monitored by fluorescence recovery after photobleaching (FRAP). A global fitting of all kinetic data determined key reaction constants of tri-snRNP assembly. The rates of di-snRNP and tri-snRNP assemblies are similar and ca 230 tri-snRNPs are assembled in one CB per minute. Tri-snRNP assembly is about ten-fold faster in CBs than in the surrounding nucleoplasm, which is fully consistent with the importance of CBs for snRNP formation in rapidly developing biological systems.
Permanent Link: http://hdl.handle.net/11104/0194107