Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
1984-1-7
pubmed:abstractText
As a subunit of bacteriophage Q beta replicase, ribosomal protein S1 is required for tight binding of the enzyme to Q beta RNA and for the initiation of Q beta RNA transcription. To compare these properties of S1 with its functions in protein synthesis, we have reconstituted altered replicase enzymes by adding discrete fragments of S1 to Q beta replicase lacking S1 (R(-S1]. We show that the NH2-terminal region of S1 is required for S1 subunit interactions in replicase since a trypsin-resistant fragment (denoted S1-F1) lacking the NH2-terminal 31% of S1 is functionally inactive and does not seem to bind to R(-S1). Previous studies with S1-F1 indicated that this NH2-terminal region is required for S1 to bind to the ribosome. Our results also show that the COOH-terminal region of S1 is dispensable for S1's function in replicase because a mutant of S1 (m1-S1) lacking 21% of the COOH-terminal portion of the chain is as active as wild type S1 in replicase and binds to R(-S1) with comparable affinity. In protein synthesis, the mutant m1-S1 is known to substitute for S1 but is only about 75% as efficient as wild type S1.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
258
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13649-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
The activity of discrete fragments of ribosomal protein S1 in Q beta replicase function.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.