TY - JOUR
T1 - A candidate U1 small nuclear RNA for trypanosomatid protozoa
AU - Schnare, Murray N.
AU - Gray, Michael W.
PY - 1999/8/20
Y1 - 1999/8/20
N2 - In trypanosomatid protozoa, all mRNAs obtain identical 5'-ends by trans- splicing of the 5'-terminal 39 nucleotides of a small spliced leader RNA to appropriate acceptor sites in pre-mRNA. Although this process involves spliceosomal small nuclear (sn) RNAs, it is thought that trypanosomatids do not contain a homolog of the cis-spliceosomal U1 snRNA. We show here that a trypanosomatid protozoon, Crithidia fasciculata, contains a novel small RNA that displays several features characteristic of a U1 snRNA, including (i) a methylguanosine cap and additional 5'-terminal modifications, (ii) a potential binding site for common core proteins that are present in other trans-spliceosomal ribonucleoproteins, (iii) a U1-like 5'-terminal sequence, and (iv) a U1-like stem/loop I structure. Because trypanosomatid pre-mRNAs do not appear to contain cis-spliced introns, we argue that this previously unrecognized RNA species is a good candidate to be a trans-spliceosomal U1 snRNA.
AB - In trypanosomatid protozoa, all mRNAs obtain identical 5'-ends by trans- splicing of the 5'-terminal 39 nucleotides of a small spliced leader RNA to appropriate acceptor sites in pre-mRNA. Although this process involves spliceosomal small nuclear (sn) RNAs, it is thought that trypanosomatids do not contain a homolog of the cis-spliceosomal U1 snRNA. We show here that a trypanosomatid protozoon, Crithidia fasciculata, contains a novel small RNA that displays several features characteristic of a U1 snRNA, including (i) a methylguanosine cap and additional 5'-terminal modifications, (ii) a potential binding site for common core proteins that are present in other trans-spliceosomal ribonucleoproteins, (iii) a U1-like 5'-terminal sequence, and (iv) a U1-like stem/loop I structure. Because trypanosomatid pre-mRNAs do not appear to contain cis-spliced introns, we argue that this previously unrecognized RNA species is a good candidate to be a trans-spliceosomal U1 snRNA.
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U2 - 10.1074/jbc.274.34.23691
DO - 10.1074/jbc.274.34.23691
M3 - Article
C2 - 10446125
AN - SCOPUS:0033588289
SN - 0021-9258
VL - 274
SP - 23691
EP - 23694
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 34
ER -