Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-1-19
pubmed:abstractText
Leu- and Met-enkephalin were the first endogenous opioid peptides identified in different mammalian species including the human. Comparative biochemical and bioinformatic evidence indicates that enkephalins are not limited to mammals. Various prodynorphin (PDYN) sequences in lower vertebrates revealed the presence of other enkephalin fingerprints in these precursor polypeptides. Among the novel enkephalins Ile-enkephalin (Tyr-Gly-Gly-Phe-Ile) was primarily observed in the African clawed frog (Xenopus laevis) PDYNs, while the structure of Phe-enkephalin (Tyr-Gly-Gly-Phe-Phe) was predicted by analyzing brain cDNA sequences encoding a PDYN of the African lungfish (Protopterus annectens). Ile-enkephalin can also be found in the PDYNs of four other fish species including the eel, bichir, zebrafish and tilapia, but no further occurrence for the Phe-enkephalin motif is available as yet. Based on sequencing data, the biological relevance of Phe- and Ile-enkephalin is suggested, because both of them can arise by regular posttranslational enzymatic processing of the respective neuropeptide precursors. In various receptor binding assays performed on rat brain membrane preparations both of the new peptides turned out to be moderate affinity opioids with a weak preference for the delta-opioid receptor (DOP) sites. Phe-enkephalin of the lungfish displayed rather unexpectedly low affinities toward the mu-opioid receptor (MOP) and DOP, while exhibiting moderate affinity toward the kappa-opioid receptor (KOP). In receptor-mediated G-protein activation assays measured by the stimulation of [(35)S]GTPgammaS binding, Met-enkephalin produced the highest stimulation followed by Leu-enkephalin, Ile-enkephalin and Phe-enkephalin, whereas the least efficacious among these endogenous peptides was still more effective than the prototype opiate agonist morphine in these functional tests.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Analgesics, Opioid, http://linkedlifedata.com/resource/pubmed/chemical/DNA, Complementary, http://linkedlifedata.com/resource/pubmed/chemical/Enkephalin, Ala(2)-MePhe(4)-Gly(5)-, http://linkedlifedata.com/resource/pubmed/chemical/Enkephalins, http://linkedlifedata.com/resource/pubmed/chemical/Guanosine 5'-O-(3-Thiotriphosphate), http://linkedlifedata.com/resource/pubmed/chemical/Naloxone, http://linkedlifedata.com/resource/pubmed/chemical/Narcotic Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Opioid Peptides, http://linkedlifedata.com/resource/pubmed/chemical/Protein Precursors, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, delta, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, mu, http://linkedlifedata.com/resource/pubmed/chemical/Tritium, http://linkedlifedata.com/resource/pubmed/chemical/preproenkephalin
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
158
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
867-74
pubmed:meshHeading
pubmed-meshheading:18977279-Analgesics, Opioid, pubmed-meshheading:18977279-Animals, pubmed-meshheading:18977279-Anura, pubmed-meshheading:18977279-Base Sequence, pubmed-meshheading:18977279-Brain, pubmed-meshheading:18977279-DNA, Complementary, pubmed-meshheading:18977279-Dose-Response Relationship, Drug, pubmed-meshheading:18977279-Enkephalin, Ala(2)-MePhe(4)-Gly(5)-, pubmed-meshheading:18977279-Enkephalins, pubmed-meshheading:18977279-Fishes, pubmed-meshheading:18977279-Guanosine 5'-O-(3-Thiotriphosphate), pubmed-meshheading:18977279-Naloxone, pubmed-meshheading:18977279-Narcotic Antagonists, pubmed-meshheading:18977279-Opioid Peptides, pubmed-meshheading:18977279-Protein Binding, pubmed-meshheading:18977279-Protein Precursors, pubmed-meshheading:18977279-Rats, pubmed-meshheading:18977279-Rats, Wistar, pubmed-meshheading:18977279-Receptors, Opioid, delta, pubmed-meshheading:18977279-Receptors, Opioid, mu, pubmed-meshheading:18977279-Tritium
pubmed:year
2009
pubmed:articleTitle
Binding studies of novel, non-mammalian enkephalins, structures predicted from frog and lungfish brain cDNA sequences.
pubmed:affiliation
Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvari krt 62, 6726 Szeged, Hungary. benyhe@brc.hu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't