Linked Life Data

6088550

Source:http://linkedlifedata.com/resource/pubmed/id/6088550

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1984-10-25
pubmed:abstractText
Spectrin in isolated erythrocyte membranes is known to undergo tetramer to dimer transformation upon hypotonic incubation at 37 degrees C. In the present study, we detect no such transformation in intact erythrocytes in which hypotonicity is achieved by valinomycin treatment followed by hypotonic swelling. The inhibition of spectrin tetramer to dimer transformation is attributable to intracellular hemoglobin, since the addition of hemoglobin to isolated membranes or spectrin extracts blocks a similar spectrin transformation. However, the inhibitory effect is not limited to hemoglobin; other proteins including heme-containing proteins and basic proteins such as cytochrome c, ribonuclease, and albumin are also effective. The magnitude of their effect is proportional to the increased pI value of these proteins. We conclude that the stabilizing effect of these proteins on spectrin tetramers under hypotonic conditions is partly due to their non-ideality, which excludes water from spectrin and thus increases the effective concentration of spectrin, and to their electrostatic interactions with spectrin. In addition, promotion of spectrin self-association by hemoglobin under hypotonic conditions increases the stability of membrane skeletons against mechanical shearing. More importantly, the hemoglobin effect on spectrin self-association is demonstrable at physiological hemoglobin concentration, pH, and osmolarity, suggesting that in intact red cells the spectrin dimer-dimer association, as well as the membrane skeletal structure, is strengthened by intracellular hemoglobin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11556-62
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Hemoglobin enhances the self-association of spectrin heterodimers in human erythrocytes.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.