Peptide YY-2 (PYY2) and pancreatic polypeptide-2 (PPY2): species-specific evolution of novel members of the neuropeptide Y gene family.
Several gene duplication events have led to the creation of at least five distinct members of the neuropeptide Y gene family. We now reveal that the most recent of these events, involving the PYY-PPY gene cluster on chromosome 17q21.1, has led to the creation of novel PYY- and PP-like genes on chromosome 17q11 in the human genome. Sequence analysis of the novel human PYY2 and PPY2 genes shows an extensive homology to the peptide YY-pancreatic polypeptide genes, at the level of gene structure, nucleotide sequence, and primary amino acid sequence. The extremely high degree of homology between the PYY-PPY and the PYY2-PPY2 gene clusters, in both coding regions and especially noncoding regions, suggests that the PYY2 and PPY2 genes have arisen by a very recent gene duplication. Similar gene duplication events of the PYY-PPY gene cluster have also occurred in other species, including cow and baboon, but have not been confirmed in the rat and mouse genomes. Interestingly, despite the greater than 92% nucleotide sequence identity between these new genes, a few specific mutations have resulted in significantly altered peptide sequences. These altered sequences are accompanied by acquisition of new functions apparently unrelated to the neurotransmitter/endocrine role of PYY and PPY, as demonstrated by the major involvement of bovine PYY2, also known as seminal plasmin, in the fertilization process.
Couzens
M
M
Neurobiology Program, Garvan Institute of Medical Research, Darlinghurst, NSW, 2010, Australia.
Liu
M
M
Tüchler
C
C
Kofler
B
B
Nessler-Menardi
C
C
Parker
R M
RM
Klocker
H
H
Herzog
H
H
D000595:Amino Acid Sequence; D000818:Animals; D015139:Blotting, Southern; D002417:Cattle; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17; D003001:Cloning, Molecular; D019143:Evolution, Molecular; D020440:Gene Duplication; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008969:Molecular Sequence Data; D009478:Neuropeptide Y / Q000235:genetics*; D010191:Pancreatic Polypeptide / Q000235:genetics* / Q000378:metabolism; D010215:Papio; D019894:Peptide YY / Q000235:genetics* / Q000378:metabolism; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029607:Seminal Vesicle Secretory Proteins; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
D009478:Neuropeptide Y; C408375:PPY2P protein, human; D011506:Proteins; D029607:Seminal Vesicle Secretory Proteins; D019894:Peptide YY; D010191:Pancreatic Polypeptide