Two variants of the pituitary specific transcription factor Pit-1 in Atlantic salmon.
We have cloned two 1.6 kb cDNAs encoding variants of the POU-type pituitary-specific transcription factor Pit-1 from Atlantic salmon. Sequence comparison with mammalian Pit-1 revealed that the POU domain was highly similar while flanking regions were less conserved. The N-terminal region contained three insertions relative to mammalian Pit-1, one of these corresponded to the insertion found in the alternatively spliced Pit-1a isoform. While two different salmon Pit-1 transcripts were expressed, alternative splicing in the 5'-region did not appear to contribute to further transcript diversity. Both salmon Pit-1 cDNAs encoded 39.5 kDa proteins that specifically bind a consensus Pit-1 recognition sequence in vitro. The salmon Pit-1 proteins also recognized the classical octamer motif; however, a point mutation in the POU homeodomain abolished this interaction.
Lorens
J B
JB
Laboratory of Biotechnology, University of Bergen, Norway.
Aasland
R
R
Brunstad
H
H
Bergh
H
H
Male
R
R
D017398:Alternative Splicing; D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D012474:Salmon; D017386:Sequence Homology, Amino Acid; D050817:Transcription Factor Pit-1; D014157:Transcription Factors / Q000235:genetics*
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D050817:Transcription Factor Pit-1; D014157:Transcription Factors; D004247:DNA