The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi
Antarctic fishes of the suborder Notothenioidei characteristically possess large stores of neutral lipids that have been shown to be important both in conferring buoyant lift and as a caloric resource for energy metabolism. Previous work has established that the aerobic energy metabolism of Antarcti...
Published in: | Journal of Experimental Biology |
---|---|
Main Authors: | , |
Format: | Text |
Language: | English |
Published: |
Company of Biologists
2004
|
Subjects: | |
Online Access: | http://jeb.biologists.org/cgi/content/short/207/6/897 https://doi.org/10.1242/jeb.00823 |
id |
fthighwire:oai:open-archive.highwire.org:jexbio:207/6/897 |
---|---|
record_format |
openpolar |
spelling |
fthighwire:oai:open-archive.highwire.org:jexbio:207/6/897 2023-05-15T13:55:31+02:00 The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi Hazel, J. R. Sidell, B. D. 2004-02-22 00:00:00.0 text/html http://jeb.biologists.org/cgi/content/short/207/6/897 https://doi.org/10.1242/jeb.00823 en eng Company of Biologists http://jeb.biologists.org/cgi/content/short/207/6/897 http://dx.doi.org/10.1242/jeb.00823 Copyright (C) 2004, Company of Biologists Research Article TEXT 2004 fthighwire https://doi.org/10.1242/jeb.00823 2015-02-28T19:55:43Z Antarctic fishes of the suborder Notothenioidei characteristically possess large stores of neutral lipids that have been shown to be important both in conferring buoyant lift and as a caloric resource for energy metabolism. Previous work has established that the aerobic energy metabolism of Antarctic fish is fueled predominantly by the catabolism of fatty acids, with the catabolic machinery displaying a preference for the oxidation of unsaturated fatty acids. The composition of the fatty acids released from adipose tissue of Antarctic fish during lipolysis, however, has not previously been demonstrated. Employing a substrate competition assay, we have characterized the substrate specificity of hormone-sensitive lipase (HSL) from adipose tissue of the Antarctic fish Trematomus newnesi . Rates of oleic acid release from radiolabeled triolein were quantified in the presence and absence of a nonradiolabeled cosubstrate. Polyunsaturated species of triacylglycerols (TAGs) containing 18:2 or 20:4 depressed rates of oleate release by 70–75% below control values. Most of the molecular species of TAG containing monoenoic fatty acids (i.e. those containing 14:1, 16:1 or 20:1) had no significant effect on rates of oleate release. By contrast, oleate release from triolein was actually stimulated (by 2–4-fold) by both saturated species of TAG (i.e. those containing 14:0, 16:0 and 18:0) and those possessing long-chain (22:1 and 24:1) monoenes (by 1.2–1.5-fold). Thus, the rank order of substrate preference for adipose tissue HSL was: polyunsaturates > monoenes > saturates. Degree of fatty acid unsaturation had a more marked effect on rates of hydrolysis than did fatty acid chain length. In addition, the enzyme displayed a preference for the hydrolysis of sn -1,2 rather than sn -1,3 diacylglycerols. These data indicate that the substrate specificity of adipose tissue HSL may be an important factor in determining which fatty acids are mobilized during stimulated lipolysis and which are made available for catabolism by other ... Text Antarc* Antarctic HighWire Press (Stanford University) Antarctic The Antarctic Journal of Experimental Biology 207 6 897 903 |
institution |
Open Polar |
collection |
HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Research Article |
spellingShingle |
Research Article Hazel, J. R. Sidell, B. D. The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
topic_facet |
Research Article |
description |
Antarctic fishes of the suborder Notothenioidei characteristically possess large stores of neutral lipids that have been shown to be important both in conferring buoyant lift and as a caloric resource for energy metabolism. Previous work has established that the aerobic energy metabolism of Antarctic fish is fueled predominantly by the catabolism of fatty acids, with the catabolic machinery displaying a preference for the oxidation of unsaturated fatty acids. The composition of the fatty acids released from adipose tissue of Antarctic fish during lipolysis, however, has not previously been demonstrated. Employing a substrate competition assay, we have characterized the substrate specificity of hormone-sensitive lipase (HSL) from adipose tissue of the Antarctic fish Trematomus newnesi . Rates of oleic acid release from radiolabeled triolein were quantified in the presence and absence of a nonradiolabeled cosubstrate. Polyunsaturated species of triacylglycerols (TAGs) containing 18:2 or 20:4 depressed rates of oleate release by 70–75% below control values. Most of the molecular species of TAG containing monoenoic fatty acids (i.e. those containing 14:1, 16:1 or 20:1) had no significant effect on rates of oleate release. By contrast, oleate release from triolein was actually stimulated (by 2–4-fold) by both saturated species of TAG (i.e. those containing 14:0, 16:0 and 18:0) and those possessing long-chain (22:1 and 24:1) monoenes (by 1.2–1.5-fold). Thus, the rank order of substrate preference for adipose tissue HSL was: polyunsaturates > monoenes > saturates. Degree of fatty acid unsaturation had a more marked effect on rates of hydrolysis than did fatty acid chain length. In addition, the enzyme displayed a preference for the hydrolysis of sn -1,2 rather than sn -1,3 diacylglycerols. These data indicate that the substrate specificity of adipose tissue HSL may be an important factor in determining which fatty acids are mobilized during stimulated lipolysis and which are made available for catabolism by other ... |
format |
Text |
author |
Hazel, J. R. Sidell, B. D. |
author_facet |
Hazel, J. R. Sidell, B. D. |
author_sort |
Hazel, J. R. |
title |
The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
title_short |
The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
title_full |
The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
title_fullStr |
The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
title_full_unstemmed |
The substrate specificity of hormone-sensitive lipase from adipose tissue of the Antarctic fish Trematomus newnesi |
title_sort |
substrate specificity of hormone-sensitive lipase from adipose tissue of the antarctic fish trematomus newnesi |
publisher |
Company of Biologists |
publishDate |
2004 |
url |
http://jeb.biologists.org/cgi/content/short/207/6/897 https://doi.org/10.1242/jeb.00823 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://jeb.biologists.org/cgi/content/short/207/6/897 http://dx.doi.org/10.1242/jeb.00823 |
op_rights |
Copyright (C) 2004, Company of Biologists |
op_doi |
https://doi.org/10.1242/jeb.00823 |
container_title |
Journal of Experimental Biology |
container_volume |
207 |
container_issue |
6 |
container_start_page |
897 |
op_container_end_page |
903 |
_version_ |
1766262180013932544 |