creators_name: Sebastian Samuel, Jesse
creators_name: Kumar, Deepak
creators_name: Babu Chodisetti, Sathi
creators_name: Agrewala, Javed N
creators_name: Singh, Balvinder
creators_name: Guptasarma, Purnananda
creators_name: Sarkar, Dibyendu
type: article
datestamp: 2016-01-29 04:05:09
lastmod: 2016-01-29 04:05:09
metadata_visibility: show
title: Probing protease sensitivity of recombinant human erythropoietin reveals α3-α4 inter-helical loop as a stability determinant.
ispublished: pub
subjects: QR
keywords: cathepsin L; circulating half-life; in vivo clearance; inter-helical loop region; proteolysis; recombinant HuEpo
note: Copyright of this article belongs to Wiley Online
abstract: Although unglycosylated HuEpo is fully functional, it has very short serum half-life. However, the mechanism of in vivo clearance of human Epo (HuEpo) remains largely unknown. In this study, the relative importance of protease-sensitive sites of recombinant HuEpo (rHuEpo) has been investigated by analysis of structural data coupled with in vivo half-life measurements. Our results identify α3-α4 inter-helical loop region as a target site of lysosomal protease Cathepsin L. Consistent with previously-reported lysosomal degradation of HuEpo, these results for the first time identify cleavage sites of rHuEpo by specific lysosomal proteases. Furthermore, in agreement with the lowered exposure of the peptide backbone around the cleavage site, remarkably substitutions of residues with bulkier amino acids result in significantly improved in vivo stability. Together, these results have implications for the mechanism of in vivo clearance of the protein in humans.
date: 2015-10
date_type: published
publication: Proteins
volume: 83
number: 10
publisher: Wiley Online
pagerange: 1813-22
refereed: TRUE
issn: 1097-0134
official_url: http://dx.doi.org/10.1002/prot.24865
citation:   Sebastian Samuel, Jesse and Kumar, Deepak and Babu Chodisetti, Sathi and Agrewala, Javed N and Singh, Balvinder and Guptasarma, Purnananda and Sarkar, Dibyendu  (2015) Probing protease sensitivity of recombinant human erythropoietin reveals α3-α4 inter-helical loop as a stability determinant.  Proteins, 83 (10).  pp. 1813-22.  ISSN 1097-0134