The University of Southampton
University of Southampton Institutional Repository

The amino acid sequences of the carboxyl termini of human and mouse hepatic lipase influence cell surface association

The amino acid sequences of the carboxyl termini of human and mouse hepatic lipase influence cell surface association
The amino acid sequences of the carboxyl termini of human and mouse hepatic lipase influence cell surface association
Human hepatic lipase (hHL) mainly exists cell surface bound, whereas mouse HL (mHL) circulates in the blood stream. Studies have suggested that the carboxyl terminus of HL mediates cell surface binding. We prepared recombinant hHL, mHL, and chimeric proteins (hHLmt and mHLht) in which the carboxyl terminal 70 amino acids of hHL were exchanged with the corresponding sequence from mHL. The hHL, mHL, and hHLmt proteins were catalytically active using triolein and tributyrin as substrates. In transfected cells, the majority of hHLs bound to the cell surface, with only 4% of total extracellular hHL released into heparin-free media, whereas under the same conditions, 61% of total extracellular mHLs were released. Like mHL, hHLmt showed decreased cell surface binding, with 68% of total extracellular hHLmt released. To determine the precise amino acid residues involved in cell surface binding, we prepared a truncated hHL mutant (hHL471) by deleting the carboxyl terminal five residues (KRKIR). The hHL471 also retained hydrolytic activity with triolein and tributyrin, and showed decreased cell surface binding, with 40% of total extracellular protein released into the heparin-free media.
These data suggest that the determinants of cell surface binding exist within the carboxyl terminal 70 amino acids of hHL, of which the last five residues play an important role.
Abbreviations: HBD, heparin binding domain; hHL, human hepatic lipase; HSPG, heparan sulfate proteoglycan; LPL, lipoprotein lipase; LRP, LDL receptor-related protein; mHL, mouse hepatic lipase; TG, triacylglycerol.
lipolysis, heparin, heparin binding domain, heparan sulfate proteoglycan, tributyrin, triolein
0022-2275
1306-1314
Brown, R.J.
c0ed9fa7-58c3-4994-9bc9-1bae70b9e203
Schultz, J.R.
553175e1-4ce5-458a-880c-cdf3ec10d510
Ko, K.W.
d825e462-3e96-4970-96ff-6487c5a410cf
Hill, J.S.
f31146d4-0142-4c80-a6a8-0ab75f24b9cc
Ramsamy, T.A.
d255172f-0d93-49c9-b015-b9dc4b7e797b
White, A.L.
91a749fd-2061-4b69-835b-4286251e7906
Sparks, D.L.
5042391f-d1c8-4cb8-8c3b-2dc5b7ca7d4f
Yao, Z.
d19f07af-939a-4c74-9651-d12a6e647565
Brown, R.J.
c0ed9fa7-58c3-4994-9bc9-1bae70b9e203
Schultz, J.R.
553175e1-4ce5-458a-880c-cdf3ec10d510
Ko, K.W.
d825e462-3e96-4970-96ff-6487c5a410cf
Hill, J.S.
f31146d4-0142-4c80-a6a8-0ab75f24b9cc
Ramsamy, T.A.
d255172f-0d93-49c9-b015-b9dc4b7e797b
White, A.L.
91a749fd-2061-4b69-835b-4286251e7906
Sparks, D.L.
5042391f-d1c8-4cb8-8c3b-2dc5b7ca7d4f
Yao, Z.
d19f07af-939a-4c74-9651-d12a6e647565

Brown, R.J., Schultz, J.R., Ko, K.W., Hill, J.S., Ramsamy, T.A., White, A.L., Sparks, D.L. and Yao, Z. (2003) The amino acid sequences of the carboxyl termini of human and mouse hepatic lipase influence cell surface association. Journal of Lipid Research, 44 (7), 1306-1314. (doi:10.1194/jlr.M200374-JLR200).

Record type: Article

Abstract

Human hepatic lipase (hHL) mainly exists cell surface bound, whereas mouse HL (mHL) circulates in the blood stream. Studies have suggested that the carboxyl terminus of HL mediates cell surface binding. We prepared recombinant hHL, mHL, and chimeric proteins (hHLmt and mHLht) in which the carboxyl terminal 70 amino acids of hHL were exchanged with the corresponding sequence from mHL. The hHL, mHL, and hHLmt proteins were catalytically active using triolein and tributyrin as substrates. In transfected cells, the majority of hHLs bound to the cell surface, with only 4% of total extracellular hHL released into heparin-free media, whereas under the same conditions, 61% of total extracellular mHLs were released. Like mHL, hHLmt showed decreased cell surface binding, with 68% of total extracellular hHLmt released. To determine the precise amino acid residues involved in cell surface binding, we prepared a truncated hHL mutant (hHL471) by deleting the carboxyl terminal five residues (KRKIR). The hHL471 also retained hydrolytic activity with triolein and tributyrin, and showed decreased cell surface binding, with 40% of total extracellular protein released into the heparin-free media.
These data suggest that the determinants of cell surface binding exist within the carboxyl terminal 70 amino acids of hHL, of which the last five residues play an important role.
Abbreviations: HBD, heparin binding domain; hHL, human hepatic lipase; HSPG, heparan sulfate proteoglycan; LPL, lipoprotein lipase; LRP, LDL receptor-related protein; mHL, mouse hepatic lipase; TG, triacylglycerol.

Full text not available from this repository.

More information

Published date: 2003
Keywords: lipolysis, heparin, heparin binding domain, heparan sulfate proteoglycan, tributyrin, triolein

Identifiers

Local EPrints ID: 26227
URI: https://eprints.soton.ac.uk/id/eprint/26227
ISSN: 0022-2275
PURE UUID: fa62e015-a1db-43ba-a576-3770bb1d7a92

Catalogue record

Date deposited: 21 Apr 2006
Last modified: 17 Jul 2017 16:08

Export record

Altmetrics

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×