In article 01HKTPLL4Y6A00048L at muwayb.ucs.unimelb.edu.au, mc_fadden at botany.unimelb.edu.au (Geoff McFadden) writes:
> What's the smallest known spliceosomal intron? So far the smallest I can
> track down is the 35bp intron in the cut7 gene of fission yeast (Nature
> 347:563-6). Does anybody know of any published (or unpublished)
> spliceosomal introns less than 35bp? My grad student and I have found a
> gene with three (apparently spliceosomal) introns of 19bp, so we may be
> claiming a new record.
I used HOVERGEN[1] search for short introns among GenBank vertebrate nuclear
protein-encoding genes.
I found 5 sequences with a least one intron (declared to be) shorter than 35bp.
These sequences are described at the end of this mail.
The shortest intron is 7 bp long!!!
What is declared in GenBank is however not necessarily carefully checked! You should
look at the original publication to verify this information.
================================================================
Laurent Duret duret at biomserv.univ-lyon1.fr
Tel: +33 72.44.81.42 Fax: +33 78.89.27.19
Laboratoire de Biometrie, Genetique et Biologie des Populations
Bat 741 - URA CNRS 243 Universite Claude Bernard - Lyon I
43, Bd du 11 Novembre 1918
69622 Villeurbanne cedex FRANCE
================================================================
[1] L. Duret, D. Mouchiroud & M. Gouy (1994) HOVERGEN: a Database of
Homologous Vertebrate Genes. Nucleic Acids Research 22:2360-2365
LOCUS HSAQUPN2 995 bp DNA PRI 21-APR-1994
DEFINITION H.sapiens gene for water channel aquaporin-2.
ACCESSION Z29491
FEATURES Location/Qualifiers
intron 431..466
/number=1
exon 467..631
/number=2
intron 632..664
/number=2
exon 665..745
/number=3
intron 746..772
/number=3
exon 773..>995
/number=4
//
LOCUS HSPVALB 1350 bp DNA PRI 24-MAR-1992
DEFINITION H.sapiens gene for parvalbumin.
ACCESSION X63578
FEATURES Location/Qualifiers
intron 542..565
/number=1
exon 566..633
/number=2
intron 634..657
/number=2
exon 658..790
/number=3
intron 791..814
/number=3
exon 815..918
/number=4
intron 919..942
/number=4
exon 943..1157
/number=5
//
LOCUS HUMRSP1GPA 1935 bp ds-DNA PRI 18-NOV-1991
DEFINITION Human pregnancy-specific glycoprotein beta-1 (SP1) gene, last 3
exons.
ACCESSION M30628
FEATURES Location/Qualifiers
exon 46..411
/gene="SP1"
/number=1
intron 412..751
/gene="SP1"
exon 752..1308
/gene="SP1"
/note="next to last exon"
/number=2
//
LOCUS MUSINTA7RS 783 bp ds-DNA ROD 09-MAR-1994
DEFINITION Mouse alpha-7 integrin gene, exons X-X3.
ACCESSION L23422
FEATURES Location/Qualifiers
exon 8..231
/note="Repeat region III exon of alpha-7 integrin gene;
putative"
intron 232..258
/note="intron X"
exon 259..390
/note="exon X1 of alpha-7 integrin gene; putative"
intron 391..421
/note="intron X1"
exon 422..541
/note="exon X2 of alpha-7 integrin gene; putative"
intron 542..558
/note="intron X2"
exon 559..766
/note="Repeat region IV exon of alpha-7 integrin gene;
putative"
intron 767..>783
/note="intron X3"
//
LOCUS RATFN3M1 2350 bp ds-DNA ROD 11-MAR-1994
DEFINITION Rat fibronectin (cell-, heparin-, and fibrin-binding domains) gene
encoding three fibronectin mRNAs, exons 1,2,3.
ACCESSION L00191 K01269 K01270 K01271
FEATURES Location/Qualifiers
exon <1..1129
/note="fibronectin 1"
/number=1
intron 1130..1141
/note="f1,f2,f3 intron A"
exon 1142..1231
/number=2
intron 1232..2204
/note="f3 intron B"
intron 1232..1919
/note="f2 intron B"
intron 1232..1844
/note="f1 intron B"
exon 1845..2311
/number=3
exon 1920..2311
/number=3
exon 2205..2311
/number=3
/product="fibronectin 3"
intron 2312..>2350
/note="f1,f2,f3 intron C"
//
