mRNAs that mature through trans-splicing in Caenorhabditis elegans have a trimethylguanosine cap at their 5' termini

1990 ◽  
Vol 10 (4) ◽  
pp. 1769-1772
Author(s):  
K Van Doren ◽  
D Hirsh

Approximately 10% of the mRNAs in the nematode Caenorhabditis elegans mature through a trans-splicing mechanism that involves the transfer of a 22-nucleotide spliced leader to the 5' end of the pre-mRNA. The spliced leader RNA exists as a small nuclear ribonucleoprotein particle and has the trimethylguanosine cap that is characteristic of eucaryotic small nuclear RNAs. We found that the trimethylguanosine cap present on the spliced leader RNA was transferred to the pre-mRNA during the trans-splicing reaction. Thereafter, the trimethylguanosine cap was maintained on the mature mRNA. This is the first example of eucaryotic cellular mRNAs possessing a trimethylguanosine cap structure.

1990 ◽  
Vol 10 (4) ◽  
pp. 1769-1772 ◽  
Author(s):  
K Van Doren ◽  
D Hirsh

Approximately 10% of the mRNAs in the nematode Caenorhabditis elegans mature through a trans-splicing mechanism that involves the transfer of a 22-nucleotide spliced leader to the 5' end of the pre-mRNA. The spliced leader RNA exists as a small nuclear ribonucleoprotein particle and has the trimethylguanosine cap that is characteristic of eucaryotic small nuclear RNAs. We found that the trimethylguanosine cap present on the spliced leader RNA was transferred to the pre-mRNA during the trans-splicing reaction. Thereafter, the trimethylguanosine cap was maintained on the mature mRNA. This is the first example of eucaryotic cellular mRNAs possessing a trimethylguanosine cap structure.


1990 ◽  
Vol 10 (4) ◽  
pp. 1764-1768
Author(s):  
R F Liou ◽  
T Blumenthal

The nematode Caenorhabditis elegans has an unusual small nuclear RNA, containing a 100-nucleotide RNA molecule, spliced leader RNA, which donates its 5' 22 nucleotides to a variety of recipient RNAs by a trans-splicing reaction. The spliced leader RNA has a 5' trimethylguanosine (TMG) cap, which becomes the 5' end of trans-spliced mRNAs. We found that mature trans-spliced mRNAs were immunoprecipitable with anti-TMG cap antibodies and that TMG-containing dinucleotides specifically competed with the trans-spliced mRNAs for antibody binding. We also found that these mRNAs retained their TMG caps throughout development and that the TMG-capped mRNAs were polysome associated. Since the large majority of C. elegans mRNAs are not trans-spliced, the addition of the spliced leader and its TMG cap to a limited group of recipient RNAs may create a functionally distinct subset of mRNAs.


1990 ◽  
Vol 10 (4) ◽  
pp. 1764-1768 ◽  
Author(s):  
R F Liou ◽  
T Blumenthal

The nematode Caenorhabditis elegans has an unusual small nuclear RNA, containing a 100-nucleotide RNA molecule, spliced leader RNA, which donates its 5' 22 nucleotides to a variety of recipient RNAs by a trans-splicing reaction. The spliced leader RNA has a 5' trimethylguanosine (TMG) cap, which becomes the 5' end of trans-spliced mRNAs. We found that mature trans-spliced mRNAs were immunoprecipitable with anti-TMG cap antibodies and that TMG-containing dinucleotides specifically competed with the trans-spliced mRNAs for antibody binding. We also found that these mRNAs retained their TMG caps throughout development and that the TMG-capped mRNAs were polysome associated. Since the large majority of C. elegans mRNAs are not trans-spliced, the addition of the spliced leader and its TMG cap to a limited group of recipient RNAs may create a functionally distinct subset of mRNAs.


2004 ◽  
Vol 24 (17) ◽  
pp. 7795-7805 ◽  
Author(s):  
Philippe Ganot ◽  
Torben Kallesøe ◽  
Richard Reinhardt ◽  
Daniel Chourrout ◽  
Eric M. Thompson

ABSTRACT trans splicing of a spliced-leader RNA (SL RNA) to the 5′ ends of mRNAs has been shown to have a limited and sporadic distribution among eukaryotes. Within metazoans, only nematodes are known to process polycistronic pre-mRNAs, produced from operon units of transcription, into mature monocistronic mRNAs via an SL RNA trans-splicing mechanism. Here we demonstrate that a chordate with a highly compact genome, Oikopleura dioica, now joins Caenorhabditis elegans in coupling trans splicing with processing of polycistronic transcipts. We identified a single SL RNA which associates with Sm proteins and has a trimethyl guanosine cap structure reminiscent of spliceosomal snRNPs. The same SL RNA, estimated to be trans-spliced to at least 25% of O. dioica mRNAs, is used for the processing of both isolated or first cistrons and downstream cistrons in a polycistronic precursor. Remarkably, intercistronic regions in O. dioica are far more reduced than those in either nematodes or kinetoplastids, implying minimal cis-regulatory elements for coupling of 3′-end formation and trans splicing.


2010 ◽  
Vol 38 (4) ◽  
pp. 1125-1130 ◽  
Author(s):  
Jonathan Pettitt ◽  
Neale Harrison ◽  
Ian Stansfield ◽  
Bernadette Connolly ◽  
Berndt Müller

Spliced leader trans-splicing occurs in many primitive eukaryotes including nematodes. Most of our knowledge of trans-splicing in nematodes stems from the model organism Caenorhabditis elegans and relatives, and from work with Ascaris. Our investigation of spliced leader trans-splicing in distantly related Dorylaimia nematodes indicates that spliced-leader trans-splicing arose before the nematode phylum and suggests that the spliced leader RNA gene complements in extant nematodes have evolved from a common ancestor with a diverse set of spliced leader RNA genes.


1997 ◽  
Vol 17 (12) ◽  
pp. 7099-7107 ◽  
Author(s):  
D Y Hwang ◽  
J B Cohen

Both experimental work and surveys of the lengths of internal exons in nature have suggested that vertebrate internal exons require a minimum size of approximately 50 nucleotides for efficient inclusion in mature mRNA. This phenomenon has been ascribed to steric interference between complexes involved in recognition of the splicing signals at the two ends of short internal exons. To determine whether U1 small nuclear ribonucleoprotein, a multicomponent splicing factor that is involved in the first recognition of splice sites, contributes to the lower size limit of vertebrate internal exons, we have taken advantage of our previous observation that U1 small nuclear RNAs (snRNAs) which bind upstream or downstream of the 5' splice site (5'SS) stimulate splicing of the upstream intron. By varying the position of U1 binding relative to the 3'SS, we show that U1-dependent splicing of the upstream intron becomes inefficient when U1 is positioned 48 nucleotides or less downstream of the 3'SS, suggesting a minimal distance between U1 and the 3'SS of approximately 50 nucleotides. This distance corresponds well to the suggested minimum size of internal exons. The results of experiments in which the 3'SS region of the reporter was duplicated suggest an optimal distance of greater than 72 nucleotides. We have also found that inclusion of a 24-nucleotide miniexon is promoted by the binding of U1 to the downstream intron but not by binding to the 5'SS. Our results are discussed in the context of models to explain constitutive splicing of small exons in nature.


1990 ◽  
Vol 9 (11) ◽  
pp. 3667-3673 ◽  
Author(s):  
P. A. Maroney ◽  
G. J. Hannon ◽  
J. A. Denker ◽  
T. W. Nilsen

1996 ◽  
Vol 12 (1) ◽  
pp. 33-40 ◽  
Author(s):  
R.E. Davis

Sign in / Sign up

Export Citation Format

Share Document