Imaging

@article{,

title = {Structured mRNAs regulate translation initiation by binding to the platform of the ribosome},

author = {S Marzi and A G Myasnikov and A Serganov and C Ehresmann and P Romby and M Yusupov and B P Klaholz},

url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17889647},

isbn = {17889647},

year  = {2007},

date = {2007-01-01},

journal = {Cell},

volume = {130},

number = {6},

pages = {1019-31},

abstract = {Gene expression can be regulated at the level of initiation of protein biosynthesis via structural elements present at the 5' untranslated region of mRNAs. These folded mRNA segments may bind to the ribosome, thus blocking translation until the mRNA unfolds. Here, we report a series of cryo-electron microscopy snapshots of ribosomal complexes directly visualizing either the mRNA structure blocked by repressor protein S15 or the unfolded, active mRNA. In the stalled state, the folded mRNA prevents the start codon from reaching the peptidyl-tRNA (P) site inside the ribosome. Upon repressor release, the mRNA unfolds and moves into the mRNA channel allowing translation initiation. A comparative structure and sequence analysis suggests the existence of a universal stand-by site on the ribosome (the 30S platform) dedicated for binding regulatory 5' mRNA elements. Different types of mRNA structures may be accommodated during translation preinitiation and regulate gene expression by transiently stalling the ribosome.},

note = {0092-8674 (Print) 

Comparative Study 

Journal Article 

Research Support, Non-U.S. Gov't},

keywords = {5' Untranslated Regions Amino Acid Sequence Base Sequence Binding Sites Cryoelectron Microscopy Escherichia coli/*genetics/metabolism Escherichia coli Proteins/chemistry/genetics/*metabolism *Gene Expression Regulation, Amino Acid  Sequence Homology, Bacterial  Models, Bacterial/chemistry/*metabolism  RNA, Messenger/*metabolism  RNA, Molecular  Molecular Sequence Data  Mutation  Nucleic Acid Conformation  *Peptide Chain Initiation, Nucleic Acid  Structural Homology, Protein  Time Factors, Ribonucleic Acid  Ribosomal Proteins/chemistry/genetics/*metabolism  Ribosomes/chemistry/*metabolism/ultrastructure  Sequence Homology, ROMBY, Transfer/metabolism  Regulatory Sequences, Translational  Protein Binding  Protein Conformation  RNA, Unité ARN},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Characterization of snRNA and snRNA-type genes in the pufferfish Fugu rubripes},

author = {E Myslinski and A Krol and P Carbon},

url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15087134},

isbn = {15087134},

year  = {2004},

date = {2004-01-01},

journal = {Gene},

volume = {330},

pages = {149-158},

abstract = {Vertebrate snRNA and snRNA-type genes occur in independent transcription units with external promoters. The transcription level from the basal promoter is enhanced by the distal sequence element DSE. This element contains almost invariably two activator submotifs, the Staf binding site and the octamer motif, recruiting the Staf and Oct-1 transcriptional activators. In the present work, database search identified 35 snRNA and snRNA-type genes in the genome sequence of the pufferfish Fugu rubripes. Sequence comparisons of promoter elements, determination of template activities by microinjection into Xenopus oocytes and DNA binding assays of the transcriptional activators led to the surprising finding that only two Fugu genes conform to the general scheme with the expected two submotifs in the DSE. Distinctively, all the other DSEs harbor a unique Staf binding site. Also striking was the observation that the tRNA(Sec), and the snRNA genes that are tandemly repeated, are transcribed from promoter-less DSEs. Evolutionary implications of these results are discussed.},

note = {0378-1119 

Journal Article},

keywords = {Amino Acid  Sequence Homology, Complementary/chemistry/genetics  DNA-Binding Proteins/metabolism  Female  Genome  Molecular Sequence Data  Oocytes/metabolism  Promoter Regions (Genetics)/genetics  Protein Binding  RNA, DNA  Sequence Homology, KROL  Amino Acid Sequence  Animals  Base Sequence  Binding Sites/genetics  Comparative Study  DNA, Nucleic Acid  Takifugu/*genetics  Transcription Factors/metabolism  Xenopus laevis, Nucleic Acid/genetics  Response Elements/genetics  Sequence Alignment  Sequence Analysis, Small Nuclear/*genetics  Regulatory Sequences, Unité ARN},

pubstate = {published},

tppubtype = {article}

}