Linked Life Data

8312391

Source:http://linkedlifedata.com/resource/pubmed/id/8312391

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1994-3-23
pubmed:abstractText
Among the intracellular proteinases, the thiol proteinases such as cathepsin B (EC 3.4.22.1), cathepsin H (EC 3.4.22.16) and cathepsin L (EC 3.4.22.15) which act at slightly acidic pHs are more likely to play an important role in lysosomal protein catabolism. Out of these, cathepsin L plays a major role primarily because it has high degradative activity on cellular and matrix proteins. However, the studies on cathepsin L in crude homogenates and subcellular fractions have always been hampered by the lack of a specific substrate to exclusively measure the activity of this proteinase. The only synthetic substrate alpha-N-benzyloxycarbonyl-L-Phe-L-Arg-4-methoxy-beta-naphthylamide (Z-Phe-Arg-NNapOMe) which is hydrolysed by cathepsin L is hydrolysed equally well by cathepsin B. This substrate was manipulated to act as a selective substrate for cathepsin L. In presence of 4 M urea at pH 5.0, cathepsin B (the only other cathepsin which also hydrolyses Z-Phe-Arg-NNapOMe) was inactivated and, therefore, under these conditions, the enzyme activity quantitated by using this substrate is only due to cathepsin L. Using this newly-developed colorimetric assay method specific for cathepsin L, the subcellular and regional distribution of this proteinase were established in goat brain tissue. About 80% cathepsin L activity was recovered in the lysosomal fraction thus establishing its lysosomal nature. Among the various brain parts, highest activity was found in cerebrum followed by cerebellum, pituitary body, pons-varolli, thalamus, medulla-oblongata and hypothalamus.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0300-9084
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
873-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
A selective colorimetric assay for cathepsin L using Z-Phe-Arg-4-methoxy-beta-naphthylamide.
pubmed:affiliation
Department of Chemistry, Kurukshetra University, Haryana, India.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't