Related Experiment Videos
Structure determination and evolution of the chicken cDNA and gene encoding prepropancreatic polypeptide
1Department of Biochemistry, Tohoku University School of Medicine, Miyagi, Japan.
Gene
|August 25, 1993
Summary
Chicken pancreatic polypeptide (cPPP) precursor shows significant C-terminal divergence from mammals due to exon 3 deletion. This supports mosaic evolution unique to pancreatic polypeptide family genes.
Area of Science:
- Molecular Evolution
- Genetics
- Biochemistry
Background:
- Previous studies showed conserved N-terminal and divergent C-terminal regions in rat and human pancreatic polypeptide (PPP) precursors.
- These differences were attributed to splice junction sliding and translational frameshift in the 3'-region of the PPP gene.
Purpose of the Study:
- To determine the nucleotide sequences of the chicken PPP (cPPP) cDNA and gene.
- To compare the cPPP sequences with those of mammalian PPP precursors.
- To further investigate the 'mosaic evolution' hypothesis in the PPP gene family.
Main Methods:
- Determination of nucleotide sequences for chicken PPP (cPPP) cDNA and gene.
- Comparative analysis of cPPP sequences with rat (rPPP) and human (hPPP) sequences.
Main Results:
- The C-terminal region of cPPP precursor is highly heterologous compared to rPPP and hPPP.
- A large deletion in exon 3 of cPPP accentuates this C-terminal heterogeneity.
- cPPP terminates in exon 3, while rPPP and hPPP terminate in exon 4, indicating altered 3'-region organization due to evolutionary mutations.
Conclusions:
- The study confirms and extends the 'mosaic evolution' concept for PPP precursors.
- Mosaic evolution appears to be a phenomenon specific to PPP genes, not shared by neuropeptide-Y or peptide-YY genes.