Linked Life Data

9020971

Source:http://linkedlifedata.com/resource/pubmed/id/9020971

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-2-27
pubmed:abstractText
All four spliceosomal small nuclear ribonucleoproteins (snRNPs) U1, U2, U4/U6 and U5 contain a common structural element called the snRNP core. This core is assembled from the common snRNP proteins and the small nuclear RNA (snRNA). We have used electron microscopy to study the structure of two intermediates of the snRNP core assembly pathway: (1) the (E.F.G) protein complex, which contains only the smallest common proteins E, F and G; and (2) the subscore of U5 snRNP, in which the U5 RNA and the common proteins D1 and D2 are bound to the (E.F.G) protein complex. The general structure of the subscore was found to resemble that of the complete snRNP core, which contains the components of the subscore plus the common proteins B/B' and D3. Both the complete snRNP core and subscore particles are globular, with diameters of 7 to 8 nm. They show a characteristic accumulation of stain at the centre. However, some subscore images showed nicked outlines not seen with the complete snRNP cores. The (E.F.G) protein complex appeared as a ring, with an outer diameter of about 7 nm and a central hole 2 nm across. The molecular dimensions of the E, F and G proteins imply that the thickness of the (E.F.G) ring structure is only about 2 nm. Comparison of the (E.F.G) structure complex with the snRNP core and subcore structures implicates that a flat side of the ring-shaped (E.F.G) complex provides the assembly site(s) for the other components of the snRNP during core assembly: first for the D1 and D2 proteins (and probably the snRNA) during subscore formation, and then for the B/B' and D3 proteins in the completion of the snRNP core particle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-94
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Electron microscopy of assembly intermediates of the snRNP core: morphological similarities between the RNA-free (E.F.G) protein heteromer and the intact snRNP core.
pubmed:affiliation
Institut für Molekularbiologie und Tumorforschung, Philipps-Universität Marburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't