title: Lipoprotein lipase isoelectric point isoforms in humans.
abstract: Lipoprotein lipase (LPL) hydrolyzes circulating triacylglycerols (TAG) into free fatty acids and glycerol. It is present in almost all tissues and its tissue-specific regulation directs the flow of circulating TAG in the body. We demonstrated in a previous study that, in rat heart and post-heparin plasma (PHP), LPL consists of a pattern of more than 8 forms of the same apparent molecular weight, but different isoelectric point (pI). In the present study we describe, for the first time, the existence of at least nine LPL pI isoforms in human PHP, with apparent pI between 6.8 and 8.6. Separation and characterization of these forms was carried out by 2DE combined with Western blotting and mass spectrometry (MALDI-TOF/MS and LC-MS/MS). Further studies are needed to discover their molecular origin, the pattern of pI isoforms in human tissues, their possible physiological functions and possible modifications of their pattern in different pathologies.
authors: Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain.
authors: Míriam
authors: M
authors: Badia-Villanueva
authors: Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain.
authors: Pere
authors: P
authors: Carulla
authors: CSIC/UAB Proteomics Laboratory, IIBB-CSIC-IDIBAPS, Barcelona, Spain.
authors: Montserrat
authors: M
authors: Carrascal
authors: CSIC/UAB Proteomics Laboratory, IIBB-CSIC-IDIBAPS, Barcelona, Spain.
authors: Joaquín
authors: J
authors: Abián
authors: Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain. Electronic address: millobera@ub.edu.
authors: Miquel
authors: M
authors: Llobera
authors: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
authors: Albert
authors: A
authors: Casanovas
authors: Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain.
authors: M
authors: M
authors: Dolores López-Tejero
mesh_terms: D000328:Adult; D000818:Animals; D015153:Blotting, Western; D002846:Chromatography, Affinity; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007526:Isoelectric Point; D008071:Lipoprotein Lipase / Q000737:chemistry* / Q000302:isolation & purification; D008297:Male; D020033:Protein Isoforms / Q000737:chemistry / Q000302:isolation & purification; D051381:Rats; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055815:Young Adult
chemical_list: D020033:Protein Isoforms; D008071:Lipoprotein Lipase
keywords: 2DE; Heparin-Sepharose affinity chromatography; LPL; Mass spectrometry; Proteomics; pI isoforms