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Extracellular cathepsin L stimulates axonal growth in neurons.

ABSTRACT: Cathepsin L, a lysosomal endopeptidase expressed in most eukaryotic cells, is a member of the papain-like family of cysteine proteases. Although commonly recognized as a lysosomal protease, cathepsin L is also secreted and involved in the degradation of extracellular matrix proteins. Previous studies demonstrated that the secretion of cathepsin L was stimulated by basic fibroblast growth factor (bFGF) and bFGF-enhanced axonal terminal sprouting of motor neurons. Based on these results, although it has never been directly investigated, we hypothesized that extracellular cathepsin L may induce axonal growth.To confirm the hypothesis, the axonal growth activity of recombinant cathepsin L was evaluated in cultured cortical and spinal cord neurons. Treatment with recombinant cathepsin L significantly enhanced axonal growth, but not dendritic growth. This result indicated that extracellular cathepsin L may act as a new neuronal network modulator.

SUBMITTER: Tohda C

PROVIDER: S-EPMC5701428 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Extracellular cathepsin L stimulates axonal growth in neurons.

Tohda Chihiro C Tohda Michihisa M

BMC research notes 20171123 1

<h4>Objective</h4>Cathepsin L, a lysosomal endopeptidase expressed in most eukaryotic cells, is a member of the papain-like family of cysteine proteases. Although commonly recognized as a lysosomal protease, cathepsin L is also secreted and involved in the degradation of extracellular matrix proteins. Previous studies demonstrated that the secretion of cathepsin L was stimulated by basic fibroblast growth factor (bFGF) and bFGF-enhanced axonal terminal sprouting of motor neurons. Based on these ...[more]

PMID: 29169406

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