Linked Life Data

9405401

Source:http://linkedlifedata.com/resource/pubmed/id/9405401

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
1998-1-22
pubmed:abstractText
The human proto-oncogene c-myc encodes two proteins, c-Myc1 and c-Myc2, from two initiation codons, CUG and AUG, respectively. It is also transcribed from four alternative promoters (P0, P1, P2, and P3), giving rise to different RNA 5'-leader sequences, the long sizes of which suggest that they must be inefficiently translated by the classical ribosome scanning mechanism. Here we have examined the influence of three c-myc mRNA 5'-leaders on the translation of chimeric myc-CAT mRNAs. We observed that in the reticulocyte rabbit lysate, these 5'-leaders lead to cap-independent translation initiation. To determine whether this kind of initiation resulted from the presence of an internal ribosome entry site (IRES), COS-7 cells were transfected with bicistronic vectors containing the different c-myc 5'-leaders in the intercistronic region. An IRES was identified, requiring elements located within the P2 leader, between nucleotides -363 and -94 upstream from the CUG start codon. This is the first demonstration of the existence of IRES-dependent translation for a proto-oncogene. This IRES could be a translation enhancer, allowing activation of c-myc expression under the control of trans-acting factors and in response to specific cell stimuli.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
32061-6
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Alternative translation of the proto-oncogene c-myc by an internal ribosome entry site.
pubmed:affiliation
INSERM U397, Endocrinologie et Communication Cellulaire, Institut Louis Bugnard, Centre Hospitalier Universitaire Rangueil, Avenue Jean Poulhès, 31403 Toulouse Cedex 04, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't