PMC:2728203 / 1348-3040
Annnotations
{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/2728203","sourcedb":"PMC","sourceid":"2728203","source_url":"https://www.ncbi.nlm.nih.gov/pmc/2728203","text":"Gene expression depends on the production of mature mRNA transcripts that must be exported from their site of synthesis in the nucleus to the cytoplasm for translation. This complex multistep process can be conveniently subdivided into three distinct stages: generation of mature mRNP export complexes in the nucleus, their equilibration between the nucleus and the cytoplasm through nuclear pore complexes (NPCs), and disassembly of the export complex in the cytoplasm that prevents its return to the nucleus.1–5 The generation of export-competent mRNPs is a prerequisite for nuclear export and represents the culmination of transcription, addition of a 5′-cap to the transcript, splicing out of introns, and cleavage and polyadenylation of the 3′-end.1,2 Following completion of these processing steps, the mature transcript must be translocated to the cytoplasm where it can interface with the translation machinery. Recent evidence indicates that mRNA synthesis, processing, and export are coordinated.2,6 This coordination is achieved via a large number of mRNA-binding proteins that interact with the transcript from transcription through translation and ultimately to its destruction. The export of mature mRNPs through NPCs is mediated primarily by an evolutionarily conserved heterodimer, termed Mex67:Mtr2 in yeast, via its transient interactions with phenylalanine glycine repeat-containing proteins of the nuclear pore called FG nucleoporins.1–3,5 When the export complex reaches the cytoplasm, the RNA helicase, Dbp5, and Gle1 mediate its disassembly, and this process has been proposed to function as a molecular ratchet that prevents the return of the mRNP to the nucleus.5,7–9","tracks":[{"project":"2_test","denotations":[{"id":"18190927-16141059-62517951","span":{"begin":512,"end":513},"obj":"16141059"},{"id":"18190927-17786152-62517951","span":{"begin":512,"end":513},"obj":"17786152"},{"id":"18190927-16682182-62517951","span":{"begin":512,"end":513},"obj":"16682182"},{"id":"18190927-16777596-62517951","span":{"begin":512,"end":513},"obj":"16777596"},{"id":"18190927-17289581-62517951","span":{"begin":512,"end":513},"obj":"17289581"},{"id":"18190927-16141059-62517952","span":{"begin":755,"end":756},"obj":"16141059"},{"id":"18190927-17786152-62517952","span":{"begin":755,"end":756},"obj":"17786152"},{"id":"18190927-17786152-62517953","span":{"begin":1008,"end":1009},"obj":"17786152"},{"id":"18190927-11909523-62517953","span":{"begin":1008,"end":1009},"obj":"11909523"},{"id":"18190927-16141059-62517954","span":{"begin":1458,"end":1459},"obj":"16141059"},{"id":"18190927-17786152-62517954","span":{"begin":1458,"end":1459},"obj":"17786152"},{"id":"18190927-16682182-62517954","span":{"begin":1458,"end":1459},"obj":"16682182"},{"id":"18190927-17289581-62517954","span":{"begin":1458,"end":1459},"obj":"17289581"},{"id":"18190927-17289581-62517955","span":{"begin":1691,"end":1692},"obj":"17289581"},{"id":"18190927-16783363-62517955","span":{"begin":1691,"end":1692},"obj":"16783363"},{"id":"18190927-16783364-62517955","span":{"begin":1691,"end":1692},"obj":"16783364"},{"id":"18190927-16820771-62517955","span":{"begin":1691,"end":1692},"obj":"16820771"}],"attributes":[{"subj":"18190927-16141059-62517951","pred":"source","obj":"2_test"},{"subj":"18190927-17786152-62517951","pred":"source","obj":"2_test"},{"subj":"18190927-16682182-62517951","pred":"source","obj":"2_test"},{"subj":"18190927-16777596-62517951","pred":"source","obj":"2_test"},{"subj":"18190927-17289581-62517951","pred":"source","obj":"2_test"},{"subj":"18190927-16141059-62517952","pred":"source","obj":"2_test"},{"subj":"18190927-17786152-62517952","pred":"source","obj":"2_test"},{"subj":"18190927-17786152-62517953","pred":"source","obj":"2_test"},{"subj":"18190927-11909523-62517953","pred":"source","obj":"2_test"},{"subj":"18190927-16141059-62517954","pred":"source","obj":"2_test"},{"subj":"18190927-17786152-62517954","pred":"source","obj":"2_test"},{"subj":"18190927-16682182-62517954","pred":"source","obj":"2_test"},{"subj":"18190927-17289581-62517954","pred":"source","obj":"2_test"},{"subj":"18190927-17289581-62517955","pred":"source","obj":"2_test"},{"subj":"18190927-16783363-62517955","pred":"source","obj":"2_test"},{"subj":"18190927-16783364-62517955","pred":"source","obj":"2_test"},{"subj":"18190927-16820771-62517955","pred":"source","obj":"2_test"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"2_test","color":"#d7ec93","default":true}]}]}}