Publication Date:
2001-03-10
Description:
Initiation of protein synthesis in eukaryotes requires recruitment of the 40S ribosomal subunit to the messenger RNA (mRNA). In most cases, this depends on recognition of a modified nucleotide cap on the 5' end of the mRNA. However, an alternate pathway uses a structured RNA element in the 5' untranslated region of the messenger or viral RNA called an internal ribosomal entry site (IRES). Here, we present a cryo-electron microscopy map of the hepatitis C virus (HCV) IRES bound to the 40S ribosomal subunit at about 20 A resolution. IRES binding induces a pronounced conformational change in the 40S subunit and closes the mRNA binding cleft, suggesting a mechanism for IRES-mediated positioning of mRNA in the ribosomal decoding center.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Spahn, C M -- Kieft, J S -- Grassucci, R A -- Penczek, P A -- Zhou, K -- Doudna, J A -- Frank, J -- GM60635/GM/NIGMS NIH HHS/ -- R37 GM29169/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2001 Mar 9;291(5510):1959-62.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Howard Hughes Medical Institute, Health Research Inc. at the, Wadsworth Center, Empire State Plaza, Albany, New York 12201-0509, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11239155" target="_blank"〉PubMed〈/a〉
Keywords:
5' Untranslated Regions/chemistry/*metabolism
;
Animals
;
Base Sequence
;
Cryoelectron Microscopy
;
Hepacivirus/genetics/*metabolism/ultrastructure
;
Image Processing, Computer-Assisted
;
Macromolecular Substances
;
Models, Molecular
;
Molecular Sequence Data
;
Nucleic Acid Conformation
;
RNA, Messenger/metabolism
;
RNA, Ribosomal, 18S/chemistry/metabolism
;
RNA, Viral/chemistry/*metabolism
;
Rabbits
;
Ribosomes/*chemistry/*metabolism/ultrastructure
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics