Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis
The fundamental molecular mechanism underlying the membrane merger steps of regulated exocytosis is highly conserved across cell types. Although involvement of Phospholipase A<sub>2</sub> (PLA<sub>2</sub>) in regulated exocytosis has long been suggested, its function or that...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-04-01
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| Series: | Cells |
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| Online Access: | https://www.mdpi.com/2073-4409/8/4/303 |
| _version_ | 1797728545976352768 |
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| author | Deepti Dabral Jens R Coorssen |
| author_facet | Deepti Dabral Jens R Coorssen |
| author_sort | Deepti Dabral |
| collection | DOAJ |
| description | The fundamental molecular mechanism underlying the membrane merger steps of regulated exocytosis is highly conserved across cell types. Although involvement of Phospholipase A<sub>2</sub> (PLA<sub>2</sub>) in regulated exocytosis has long been suggested, its function or that of its metabolites—a lyso-phospholipid and a free fatty acid—remain somewhat speculative. Here, using a combined bioinformatics and top-down discovery proteomics approach, coupled with lipidomic analyses, PLA<sub>2</sub> were found to be associated with release-ready cortical secretory vesicles (CV) that possess the minimal molecular machinery for docking, Ca<sup>2+</sup> sensing and membrane fusion. Tightly coupling the molecular analyses with well-established quantitative fusion assays, we show for the first time that inhibition of a CV surface calcium independent intracellular PLA<sub>2</sub> and a luminal secretory PLA<sub>2</sub> significantly reduce docking/priming in the late steps of regulated exocytosis, indicating key regulatory roles in the critical step(s) preceding membrane merger. |
| first_indexed | 2024-03-12T11:15:36Z |
| format | Article |
| id | doaj.art-46f452206512415489fbe6589d31d2a1 |
| institution | Directory Open Access Journal |
| issn | 2073-4409 |
| language | English |
| last_indexed | 2024-03-12T11:15:36Z |
| publishDate | 2019-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Cells |
| spelling | doaj.art-46f452206512415489fbe6589d31d2a12023-09-02T02:08:23ZengMDPI AGCells2073-44092019-04-018430310.3390/cells8040303cells8040303Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered ExocytosisDeepti Dabral0Jens R Coorssen1Molecular Physiology and Molecular Medicine Research Group, School of Medicine, Western Sydney University, Campbelltown Campus, NSW 2560, AustraliaDepartment of Health Sciences, Faculty of Applied Health Sciences and Department of Biological Sciences, Faculty of Mathematics & Science, Brock University, St. Catharines, ON L2S 3A1, CanadaThe fundamental molecular mechanism underlying the membrane merger steps of regulated exocytosis is highly conserved across cell types. Although involvement of Phospholipase A<sub>2</sub> (PLA<sub>2</sub>) in regulated exocytosis has long been suggested, its function or that of its metabolites—a lyso-phospholipid and a free fatty acid—remain somewhat speculative. Here, using a combined bioinformatics and top-down discovery proteomics approach, coupled with lipidomic analyses, PLA<sub>2</sub> were found to be associated with release-ready cortical secretory vesicles (CV) that possess the minimal molecular machinery for docking, Ca<sup>2+</sup> sensing and membrane fusion. Tightly coupling the molecular analyses with well-established quantitative fusion assays, we show for the first time that inhibition of a CV surface calcium independent intracellular PLA<sub>2</sub> and a luminal secretory PLA<sub>2</sub> significantly reduce docking/priming in the late steps of regulated exocytosis, indicating key regulatory roles in the critical step(s) preceding membrane merger.https://www.mdpi.com/2073-4409/8/4/303membrane mergersecretory vesicleslysolipidsfree fatty acidsregulated secretionfusion |
| spellingShingle | Deepti Dabral Jens R Coorssen Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis Cells membrane merger secretory vesicles lysolipids free fatty acids regulated secretion fusion |
| title | Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis |
| title_full | Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis |
| title_fullStr | Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis |
| title_full_unstemmed | Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis |
| title_short | Combined Targeted Omic and Functional Assays Identify Phospholipases A<sub>2</sub> that Regulate Docking/Priming in Calcium-Triggered Exocytosis |
| title_sort | combined targeted omic and functional assays identify phospholipases a sub 2 sub that regulate docking priming in calcium triggered exocytosis |
| topic | membrane merger secretory vesicles lysolipids free fatty acids regulated secretion fusion |
| url | https://www.mdpi.com/2073-4409/8/4/303 |
| work_keys_str_mv | AT deeptidabral combinedtargetedomicandfunctionalassaysidentifyphospholipasesasub2subthatregulatedockingprimingincalciumtriggeredexocytosis AT jensrcoorssen combinedtargetedomicandfunctionalassaysidentifyphospholipasesasub2subthatregulatedockingprimingincalciumtriggeredexocytosis |