Linked Life Data

10598579

Source:http://linkedlifedata.com/resource/pubmed/id/10598579

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2000-1-10
pubmed:abstractText
Mel 1a melatonin receptors belong to the super-family of guanine nucleotide-binding regulatory protein (G protein)-coupled receptors. So far, interest in Mel 1a receptor signaling has focused mainly on the modulation of the adenylyl cyclase pathway via pertussis toxin (PTX)-sensitive G proteins. To further investigate signaling of the human Mel 1a receptor, we have developed an antibody directed against the C terminus of this receptor. This antibody detected the Mel 1a receptor as a protein with an apparent molecular mass of approximately 60 kDa in immunoblots after separation by SDS-PAGE. It also specifically precipitated the 2-[125I]iodomelatonin (125I-Mel)-labeled receptor from Mel 1a-transfected HEK 293 cells. Coprecipitation experiments showed that G(i2), G(i3), and G(q/11) proteins couple to the Mel 1a receptor in an agonist-dependent and guanine nucleotide-sensitive manner. Coupling was selective since other G proteins present in HEK 293 cells, (G(i1), G(o), G(s), G(z), and G12) were not detected in receptor complexes. Coupling of the Mel 1a receptor to G(i) and G(q) was confirmed by inhibition of high-affinity 125I-Mel binding to receptors with subtype-selective G protein alpha-subunit antibodies. G(i2) and/or G(i3) mediated adenylyl cyclase inhibition while G(q/11) induced a transient elevation in cytosolic calcium concentrations in HEK 293 cells stably expressing Mel 1a receptors. Melatonin-induced cytosolic calcium mobilization via PTX-insensitive G proteins was confirmed in primary cultures of ovine pars tuberalis cells endogenously expressing Mel 1a receptors. In conclusion, we report the development of the first antibody recognizing the cloned human Mel 1a melatonin receptor protein. We show that Mel 1a receptors functionally couple to both PTX-sensitive and PTX-insensitive G proteins. The previously unknown signaling of Mel 1a receptors through G(q/11) widens the spectrum of potential targets for melatonin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2025-38
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10598579-Adenylate Cyclase, pubmed-meshheading:10598579-Adenylate Cyclase Toxin, pubmed-meshheading:10598579-Amino Acid Sequence, pubmed-meshheading:10598579-Animals, pubmed-meshheading:10598579-Calcium, pubmed-meshheading:10598579-Cell Line, pubmed-meshheading:10598579-Cells, Cultured, pubmed-meshheading:10598579-Cytosol, pubmed-meshheading:10598579-Humans, pubmed-meshheading:10598579-Melatonin, pubmed-meshheading:10598579-Molecular Sequence Data, pubmed-meshheading:10598579-Molecular Weight, pubmed-meshheading:10598579-Pertussis Toxin, pubmed-meshheading:10598579-Pituitary Gland, Anterior, pubmed-meshheading:10598579-Receptors, Cell Surface, pubmed-meshheading:10598579-Receptors, Cytoplasmic and Nuclear, pubmed-meshheading:10598579-Receptors, Melatonin, pubmed-meshheading:10598579-Sheep, pubmed-meshheading:10598579-Signal Transduction, pubmed-meshheading:10598579-Solubility, pubmed-meshheading:10598579-Transfection, pubmed-meshheading:10598579-Virulence Factors, Bordetella
pubmed:year
1999
pubmed:articleTitle
Dual signaling of human Mel1a melatonin receptors via G(i2), G(i3), and G(q/11) proteins.
pubmed:affiliation
CNRS-UPR 0415 and Université Paris VII, Institut Cochin de Génétique Moléculaire, Paris, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't