High impact information on LOC395564

• NPY belongs to a family of 36-amino acid peptides that also includes pancreatic polypeptide and the endocrine gut peptide YY as well as the fish pancreatic peptide Y [1].
• Insulin, glucagon and somatostatin cells and cells with pancreatic polypeptide-like immunoreactivity differentiated in the pancreatic controls [2].
• The PPY/PPU tract contains specific binding sites for single- and double-stranded DNA binding proteins and, with 8 bp 3' of the tract, can function as a promoter [3].
• In hepatocytes transiently transfected with plasmids containing triiodothyronine response elements and a minimal promoter from the malic enzyme gene linked to the chloramphenicol acetyltransferase gene, deletion of the PPY/PPU tract inhibited chloramphenicol acetyltransferase activity by about 90% with or without triiodothyronine [3].
• Glucagon was isolated from a side fraction generated during the preparation of insulin and the new pancreatic peptide, avian pancreatic polypeptide from chicken pancreas [4].

Biological context of LOC395564

• Reversible dimerization of avian pancreatic polypeptide [5].
• Although the amino acid sequence of members of the pancreatic polypeptide (PP)-family of regulatory peptides has been poorly conserved during vertebrate evolution, the overall length of the peptides (36 amino acid residues) has remained constant [6].
• Tissue distribution of avian pancreatic polypeptide-degrading activity [7].
• Nucleotide sequence analysis of cloned cDNAs and/or genomic fragments has shown the PP-related sequence immediately follows the signal peptide in the prepropeptides [6].
• Affinity for cerebellar membranes was virtually equivalent for the synthetic peptide LPLRFamide and FRMFamide; the binding affinities (IC50) of all fragments tested (C-terminal pentapeptides of avian PP and NPY, and FMRFamide and LPLRFamide) fell in the same approximate range [8].

Anatomical context of LOC395564

• Pancreatic endocrine cells arise from endoderm: glucagon, insulin, and somatostatin cells differentiate early, PP cells later [9].
• Enhanced lipolysis from broiler adipocytes pretreated with pancreatic polypeptide [10].
• In the anuran Xenopus laevis, IGF-I immunoreactivity was present in islet cells showing coexistence of GLUC and PP immunoreactivities [11].
• In PP-cells immunoreactivity against the anti-serotonin serum was stronger in secretory granules than in the cytoplasmic matrix, whereas immunoreaction with the anti-AADC serum was observed to be more intense in the cytoplasmic matrix [12].

Associations of LOC395564 with chemical compounds

• In spite of its short polypeptide chain, the pancreatic polypeptide molecule consists of a polyproline II type helix and alpha-helix [13].
• A comparison of the amino acid sequence of avian PP with that of the bovine and canine homologues, which also exhibit pH-dependent dimerization [Noelken, M.E., Chang, P.J. & Kimmel, J.R. (1980) Biochemistry (preceding paper in this issue)], shows that they have three carboxylate and two guanidinium groups in common [5].
• The presence of an additional alanine residue at the NH2-terminus of the peptide suggests that the site of cleavage of the signal peptide in chicken preproPYY is different from the site of cleavage in other PP-family prepropeptides [6].
• However, sequencing of chicken PP using modem automated gas-phase sequencing technology has revealed that the original primary structure is incorrect in that residue 22 is Asn and that residue 23 is Asp [14].
• Coexistence of pancreatic polypeptide and substance P in the chicken retina [15].

Other interactions of LOC395564

• Islets contain somatostatin and pancreatic polypeptide (PP) cells, both of which also occur scattered in the exocrine parenchyma [9].
• The antibody used is C-terminal-specific and shows slight but significant (1-2%) cross-reactivity with chicken pancreatic polypeptide (APP) [16].

Analytical, diagnostic and therapeutic context of LOC395564

• To understand the stability and formation of the alpha-helical region, we prepared some peptide fragments including the helical segment of chicken pancreatic polypeptide and studied their conformations by circular dichroism (CD) [13].
• The dimerization of avian pancreatic polypeptide (PP) was studied by large-zone gel chromatography using integral boundary analysis [5].
• Effects of hypophysectomy on plasma levels of pancreatic polypeptide (APP) and insulin in adult chickens [17].
• Evidence presented herein indicates that pancreatic polypeptide is the only pancreatic hormone to be eliminated from the circulation after pancreatectomy in chickens [18].
• Immunoassay for avian pancreatic polypeptide and applications in chickens [19].

References