Perispeckles are major assembly sites for the exon junction core complex

被引：46

作者：

Daguenet, Elisabeth ^{[1
]}

Baguet, Aurelie ^{[1
]}

Degot, Sebastien ^{[1
]}

Schmidt, Ute ^{[2
]}

Alpy, Fabien ^{[1
]}

Wendling, Corinne ^{[1
]}

Spiegelhalter, Coralie ^{[1
]}

Kessler, Pascal ^{[1
]}

Rio, Marie-Christine ^{[1
]}

Le Hir, Herve ^{[3
]}

Bertrand, Edouard ^{[2
]}

Tomasetto, Catherine ^{[1
]}

机构：

[1] Univ Strasbourg, Inst Genet & Biol Mol & Cellulaire, Unite Mixte Rech 7104, Ctr Natl Rech Sci,U964 Inst Natl Sante & Rech Med, F-67404 Illkirch Graffenstaden, France

[2] Ctr Natl Rech Sci, Inst Genet Mol Montpellier, Unite Mixte Rech 5535, F-34293 Montpellier 5, France

[3] Ecole Normale Super, Inst Biol, Ctr Natl Rech Sci, Unite Mixte Rech 8197, F-75230 Paris 05, France

来源：

MOLECULAR BIOLOGY OF THE CELL | 2012年 / 23卷 / 09期

关键词：

MESSENGER-RNA DECAY; INTERCHROMATIN GRANULE CLUSTERS; NONSENSE-MEDIATED DECAY; GENE-EXPRESSION; NUCLEAR SPECKLES; MAMMALIAN-CELLS; IN-VIVO; RIBONUCLEOPROTEIN-PARTICLES; METASTATIC LYMPH-NODE-51; PERICHROMATIN FIBRILS;

D O I：

10.1091/mbc.E12-01-0040

中图分类号：

Q2 [细胞生物学];

学科分类号：

071009 ; 090102 ;

摘要：

The exon junction complex (EJC) is loaded onto mRNAs as a consequence of splicing and regulates multiple posttranscriptional events. MLN51, Magoh, Y14, and eIF4A3 form a highly stable EJC core, but where this tetrameric complex is assembled in the cell remains unclear. Here we show that EJC factors are enriched in domains that we term perispeckles and are visible as doughnuts around nuclear speckles. Fluorescence resonance energy transfer analyses and EJC assembly mutants show that perispeckles do not store free subunits, but instead are enriched for assembled cores. At the ultrastructural level, perispeckles are distinct from interchromatin granule clusters that may function as storage sites for splicing factors and intermingle with perichromatin fibrils, where nascent RNAs and active RNA Pol II are present. These results support a model in which perispeckles are major assembly sites for the tetrameric EJC core. This subnuclear territory thus represents an intermediate region important for mRNA maturation, between transcription sites and splicing factor reservoirs and assembly sites.

引用

页码：1765 / 1782

页数：18

共 94 条

[1] Structure of the exon junction core complex with a trapped DEAD-box ATPase bound to RNA [J].