Linked Life Data

9553084

Source:http://linkedlifedata.com/resource/pubmed/id/9553084

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
1998-5-22
pubmed:abstractText
Glucagon is a peptide hormone that plays a central role in the maintenance of normal circulating glucose levels. Structure-activity studies have previously demonstrated the importance of histidine at position 1 and the absolute requirement for aspartic acid at position 9 for transduction of the hormonal signal. Site-directed mutagenesis of the receptor protein identified Asp64 on the extracellular N-terminal tail to be crucial for the recognition function of the receptor. In addition, antibodies generated against aspartic acid-rich epitopes from the extracellular region competed effectively with glucagon for receptor sites, which suggested that negative charges may line the putative glucagon binding pocket in the receptor. These observations led to the idea that positively charged residues on the hormone may act as counterions to these sites. Based on these initial findings, we synthesized glucagon analogs in which basic residues at positions 12, 17, and 18 were replaced with neutral or acidic residues to examine the effect of altering the positive charge on those sites on binding and adenylyl cyclase activity. The results indicate that unlike N-terminal histidine, Lys12, Arg17, and Arg18 of glucagon have very large effects on receptor binding and transduction of the hormonal signal, although they are not absolutely critical. They contribute strongly to the stabilization of the binding interaction with the glucagon receptor that leads to maximum biological potency.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10308-12
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Positively charged residues at positions 12, 17, and 18 of glucagon ensure maximum biological potency.
pubmed:affiliation
Rockefeller University, New York, New York 10021, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.