Isoform-specific exon skipping in a variant form of ClC-2.
A new form of the widely expressed, volume-regulated chloride channel, ClC-2, has been cloned from a pig ileal cDNA library. This ClC-2 homologue, called ClC-2i, has interesting variability within its cDNA sequence, including the deletion of bases that correspond to positions 1326 through 1401 in rat ClC-2 cDNA sequence. This 75 bp deletion corresponds to the complete loss of exon 13 plus the first four bases of exon 14, and involves an atypical intron-exon splice site. Tissue-specific mRNA expression patterns in the pig show variable degrees of exon 13 skipping in ClC-2i. Exon 13 skipping was also observed in rat ClC-2i, albeit at a higher frequency than in the pig in tissues that were examined. A relatively purine-rich 76 bp insertion in the pig genomic sequence of ClC-2i, close to the 3' end of intron 12, may be responsible for the relatively high frequency of exon 13 skipping during the processing of this mRNA.
Loewen
M E
ME
Veterinary Physiological Sciences, University of Saskatchewan, 52 Campus Driv, Sask. S7N 5B4, Saskatoon, Canada.
MacDonald
D W
DW
Gaspar
K J
KJ
Forsyth
G W
GW
D000818:Animals; D001483:Base Sequence; D000090007:CLC-2 Chloride Channels; D018118:Chloride Channels / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry; D005091:Exons; D015723:Gene Library; D007082:Ileum / Q000378:metabolism; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D013552:Swine
D000090007:CLC-2 Chloride Channels; D018118:Chloride Channels; D018076:DNA, Complementary; D020033:Protein Isoforms; D012333:RNA, Messenger