Linked Life Data

7909809

Source:http://linkedlifedata.com/resource/pubmed/id/7909809

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1994-6-9
pubmed:abstractText
It has previously been reported that alpha crystallin (alpha) a major lens protein composed of alpha A and alpha B subunits, can act as a chaperone interacting with other proteins to prevent heat-induced insolubilization. It is now shown that with gamma (gamma), beta L (beta L), and beta H (beta H), other major crystallin groups, this interaction occurs exclusively with soluble denatured protein. Based on studies primarily conducted with the gamma and the beta L crystallins, there is at least one binding site per alpha monomer (alpha m). This conclusion is derived from the following evidence. The binding of soluble denatured protein to alpha increases in a linear stoichiometric manner until a 1:1 ratio of alpha m to gamma or to the presumed (beta L)m is achieved. This is based upon determination of the apparent molecular weight of the alpha-denatured protein aggregate with a calibrated TSK-G4000 SW column and on the determination of the relative masses from the areas of the aggregate peak and those of the reactants. SDS-polyacrylamide gel electrophoresis confirms that the aggregates contain the presumed components following reaction with either gamma, beta L, or beta H. Studies in which gamma or beta L crystallins have been independently heat denatured indicate that species representing 50% of the gamma population and 30% of beta L population have not heat denatured under the conditions employed. When the abundance of the denatured soluble protein exceeds that of the alpha subunits present in the macromolecular complex, further interaction occurs leading to a loss of solubility of the complex. A small increase in the size of the complex remaining in solution is also observed. The results contribute to understanding earlier observations that soluble native low molecular weight alpha species cannot be found in the inner regions of old human lenses but have shifted to large aggregates containing other crystallin components. The work tentatively suggests that the interaction rates of alpha with denatured soluble crystallins are gamma > beta L > beta H.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13601-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
The chaperone activity of bovine alpha crystallin. Interaction with other lens crystallins in native and denatured states.
pubmed:affiliation
Department of Ophthalmology, College of Physicians & Surgeons of Columbia University, New York, New York 10032.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't