A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA
It has been known for almost a decade and a half that in trypanosomes all mRNAs are trans-spliced by addition to the 5' end of the spliced leader (SL) sequence. During the same time period the conviction developed that classical cis-splicing introns are not present in the trypanosome genome and...
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2000
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_13558382_v6_n2_p163_Mair http://hdl.handle.net/20.500.12110/paper_13558382_v6_n2_p163_Mair |
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paper:paper_13558382_v6_n2_p163_Mair2023-06-08T16:11:13Z A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA Introns Kinetoplastidae Poly(A) polymerase Trans-splicing Trypanosoma brucei Trypanosoma cruzi amino acid messenger RNA polynucleotide adenylyltransferase protozoal RNA spliced leader RNA amino acid sequence article Euglena gracilis gene isolation intron nucleotide sequence point mutation priority journal RNA analysis RNA metabolism structural gene Trypanosoma Trypanosoma brucei Trypanosoma cruzi Amino Acid Sequence Animals Base Sequence Conserved Sequence DNA Primers DNA, Protozoan Exons Genes, Protozoan Introns Molecular Sequence Data Phylogeny Point Mutation Polynucleotide Adenylyltransferase RNA Precursors RNA Splicing RNA, Protozoan Trypanosoma brucei brucei Trypanosoma cruzi Euglena gracilis Eukaryota Protozoa Trypanosoma Trypanosoma brucei Trypanosoma cruzi It has been known for almost a decade and a half that in trypanosomes all mRNAs are trans-spliced by addition to the 5' end of the spliced leader (SL) sequence. During the same time period the conviction developed that classical cis-splicing introns are not present in the trypanosome genome and that the trypanosome gene arrangement is highly compact with small intergenic regions separating one gene from the next. We have now discovered that these tenets are no longer true. Poly(A) polymerase (PAP) genes in Trypanosoma brucei and Trypanosoma cruzi are split by intervening sequences of 653 and 302 nt, respectively. The intervening sequences occur at identical positions in both organisms and obey the GT/AG rule of cis-splicing introns. PAP mRNAs are trans-spliced at the very 5' end as well as internally at the 3' splice site of the intervening sequence. Interestingly, 11 nucleotide positions past the actual 5' splice site are conserved between the T. brucei and T. cruzi introns. Point mutations in these conserved positions, as well as in the AG dinucleotide of the 3' splice site, abolish intron removal in vivo. Our results, together with the recent discovery of cis-splicing introns in Euglena gracilis, suggest that both trans- and cis-splicing are ancient acquisitions of the eukaryotic cell. 2000 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_13558382_v6_n2_p163_Mair http://hdl.handle.net/20.500.12110/paper_13558382_v6_n2_p163_Mair |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Introns Kinetoplastidae Poly(A) polymerase Trans-splicing Trypanosoma brucei Trypanosoma cruzi amino acid messenger RNA polynucleotide adenylyltransferase protozoal RNA spliced leader RNA amino acid sequence article Euglena gracilis gene isolation intron nucleotide sequence point mutation priority journal RNA analysis RNA metabolism structural gene Trypanosoma Trypanosoma brucei Trypanosoma cruzi Amino Acid Sequence Animals Base Sequence Conserved Sequence DNA Primers DNA, Protozoan Exons Genes, Protozoan Introns Molecular Sequence Data Phylogeny Point Mutation Polynucleotide Adenylyltransferase RNA Precursors RNA Splicing RNA, Protozoan Trypanosoma brucei brucei Trypanosoma cruzi Euglena gracilis Eukaryota Protozoa Trypanosoma Trypanosoma brucei Trypanosoma cruzi |
| spellingShingle |
Introns Kinetoplastidae Poly(A) polymerase Trans-splicing Trypanosoma brucei Trypanosoma cruzi amino acid messenger RNA polynucleotide adenylyltransferase protozoal RNA spliced leader RNA amino acid sequence article Euglena gracilis gene isolation intron nucleotide sequence point mutation priority journal RNA analysis RNA metabolism structural gene Trypanosoma Trypanosoma brucei Trypanosoma cruzi Amino Acid Sequence Animals Base Sequence Conserved Sequence DNA Primers DNA, Protozoan Exons Genes, Protozoan Introns Molecular Sequence Data Phylogeny Point Mutation Polynucleotide Adenylyltransferase RNA Precursors RNA Splicing RNA, Protozoan Trypanosoma brucei brucei Trypanosoma cruzi Euglena gracilis Eukaryota Protozoa Trypanosoma Trypanosoma brucei Trypanosoma cruzi A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| topic_facet |
Introns Kinetoplastidae Poly(A) polymerase Trans-splicing Trypanosoma brucei Trypanosoma cruzi amino acid messenger RNA polynucleotide adenylyltransferase protozoal RNA spliced leader RNA amino acid sequence article Euglena gracilis gene isolation intron nucleotide sequence point mutation priority journal RNA analysis RNA metabolism structural gene Trypanosoma Trypanosoma brucei Trypanosoma cruzi Amino Acid Sequence Animals Base Sequence Conserved Sequence DNA Primers DNA, Protozoan Exons Genes, Protozoan Introns Molecular Sequence Data Phylogeny Point Mutation Polynucleotide Adenylyltransferase RNA Precursors RNA Splicing RNA, Protozoan Trypanosoma brucei brucei Trypanosoma cruzi Euglena gracilis Eukaryota Protozoa Trypanosoma Trypanosoma brucei Trypanosoma cruzi |
| description |
It has been known for almost a decade and a half that in trypanosomes all mRNAs are trans-spliced by addition to the 5' end of the spliced leader (SL) sequence. During the same time period the conviction developed that classical cis-splicing introns are not present in the trypanosome genome and that the trypanosome gene arrangement is highly compact with small intergenic regions separating one gene from the next. We have now discovered that these tenets are no longer true. Poly(A) polymerase (PAP) genes in Trypanosoma brucei and Trypanosoma cruzi are split by intervening sequences of 653 and 302 nt, respectively. The intervening sequences occur at identical positions in both organisms and obey the GT/AG rule of cis-splicing introns. PAP mRNAs are trans-spliced at the very 5' end as well as internally at the 3' splice site of the intervening sequence. Interestingly, 11 nucleotide positions past the actual 5' splice site are conserved between the T. brucei and T. cruzi introns. Point mutations in these conserved positions, as well as in the AG dinucleotide of the 3' splice site, abolish intron removal in vivo. Our results, together with the recent discovery of cis-splicing introns in Euglena gracilis, suggest that both trans- and cis-splicing are ancient acquisitions of the eukaryotic cell. |
| title |
A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| title_short |
A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| title_full |
A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| title_fullStr |
A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| title_full_unstemmed |
A new twist in trypanosome RNA metabolism: Cis-splicing of pre-mRNA |
| title_sort |
new twist in trypanosome rna metabolism: cis-splicing of pre-mrna |
| publishDate |
2000 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_13558382_v6_n2_p163_Mair http://hdl.handle.net/20.500.12110/paper_13558382_v6_n2_p163_Mair |
| _version_ |
1768545707322507264 |