The University of Southampton
University of Southampton Institutional Repository

Phosphatidylinositol-5-phosphate 4-kinases regulate cellular lipid metabolism by facilitating autophagy

Phosphatidylinositol-5-phosphate 4-kinases regulate cellular lipid metabolism by facilitating autophagy
Phosphatidylinositol-5-phosphate 4-kinases regulate cellular lipid metabolism by facilitating autophagy

While the majority of phosphatidylinositol-4, 5-bisphosphate (PI-4, 5-P2) in mammalian cells is generated by the conversion of phosphatidylinositol-4-phosphate (PI-4-P) to PI-4, 5-P2, a small fraction can be made by phosphorylating phosphatidylinositol-5-phosphate (PI-5-P). The physiological relevance of this second pathway is not clear. Here, we show that deletion of the genes encoding the two most active enzymes in this pathway, Pip4k2a and Pip4k2b, in the liver of mice causes a large enrichment in lipid droplets and in autophagic vesicles during fasting. These changes are due to a defect in the clearance of autophagosomes that halts autophagy and reduces the supply of nutrients salvaged through this pathway. Similar defects in autophagy are seen in nutrient-starved Pip4k2a−/−Pip4k2b−/− mouse embryonic fibroblasts and in C. elegans lacking the PI5P4K ortholog. These results suggest that this alternative pathway for PI-4, 5-P2 synthesis evolved, in part, to enhance the ability of multicellular organisms to survive starvation. Lundquist et al. reveal a critical evolutionarily conserved function of the PI5P4K family of enzymes in autophagy. PI5P4Ks generate PI-4, 5-P2 from the minor lipid PI-5-P and are required for autophagosome-lysosome fusion during metabolic stress. Importantly, this study sheds light on the anti-cancer mechanism of PI5P4K inhibition.

autophagy, lipid kinase, lysosome, metabolism, mTORC1, phospholipid, PI5P4K, TFEB
1097-2765
531–544.e9
Lundquist, Mark R.
24d58286-04b5-4480-b95c-3d4470faabf6
Goncalves, Marcus D.
a135e807-930d-4a13-925c-258704c2a233
Loughran, Ryan M.
cc830ecd-c5b5-4a8f-b0e6-9684f9e67384
Possik, Elite
7ba3f397-2fa5-4a0c-b601-a5acaf963e30
Vijayaraghavan, Tarika
523e1bb5-fd56-4b8b-8e48-74f7d6a33ddc
Yang, Annan
57cfdffd-4c4a-4030-881b-093c3ea556d3
Pauli, Chantal
efb18886-c5de-42a9-bec6-a88f71db63e1
Ravi, Archna
2db63fff-d2ad-4ef6-8cb8-c4f37d43abf9
Verma, Akanksha
4a3a58bb-1a57-4a19-8b9c-85de42eb379b
Yang, Zhiwei
45c7c435-794f-4610-ab59-4725a3255e40
Johnson, Jared L.
258c2e88-7fea-47d2-87c5-aad0dee52ef7
Wong, Jenny C.Y.
b643f45b-1fae-42af-a9c1-22a2c39b3481
Ma, Yilun
1f407bce-ad7c-405d-bd35-9e4e0be5931e
Hwang, Katie Seo Kyoung
dc5ed68c-146b-464f-93e7-a15ad49485e0
Weinkove, David
639dac22-5adf-4692-87f6-f52dde0c0d95
Divecha, Nullin
5c2ad0f8-4ce7-405f-8a15-2fc4ab96d787
Asara, John M.
9c74d661-06fc-4e36-a1b7-468f36de98ff
Elemento, Olivier
ed73e4f3-f73f-4593-996f-9dd8c42b7844
Rubin, Mark A.
1568aafa-8b43-48c9-af20-a3d150dd4891
Kimmelman, Alec C.
92ae7744-56bf-490b-83b3-5a7bea5b3dee
Pause, Arnim
e1f34ade-9c25-4647-8c61-b8d4a9405848
Cantley, Lewis C.
72b55d5f-31ed-4849-9271-60213c33f473
Emerling, Brooke M.
1e2f687f-af92-48cf-a0b5-ce968a1bcf60
Lundquist, Mark R.
24d58286-04b5-4480-b95c-3d4470faabf6
Goncalves, Marcus D.
a135e807-930d-4a13-925c-258704c2a233
Loughran, Ryan M.
cc830ecd-c5b5-4a8f-b0e6-9684f9e67384
Possik, Elite
7ba3f397-2fa5-4a0c-b601-a5acaf963e30
Vijayaraghavan, Tarika
523e1bb5-fd56-4b8b-8e48-74f7d6a33ddc
Yang, Annan
57cfdffd-4c4a-4030-881b-093c3ea556d3
Pauli, Chantal
efb18886-c5de-42a9-bec6-a88f71db63e1
Ravi, Archna
2db63fff-d2ad-4ef6-8cb8-c4f37d43abf9
Verma, Akanksha
4a3a58bb-1a57-4a19-8b9c-85de42eb379b
Yang, Zhiwei
45c7c435-794f-4610-ab59-4725a3255e40
Johnson, Jared L.
258c2e88-7fea-47d2-87c5-aad0dee52ef7
Wong, Jenny C.Y.
b643f45b-1fae-42af-a9c1-22a2c39b3481
Ma, Yilun
1f407bce-ad7c-405d-bd35-9e4e0be5931e
Hwang, Katie Seo Kyoung
dc5ed68c-146b-464f-93e7-a15ad49485e0
Weinkove, David
639dac22-5adf-4692-87f6-f52dde0c0d95
Divecha, Nullin
5c2ad0f8-4ce7-405f-8a15-2fc4ab96d787
Asara, John M.
9c74d661-06fc-4e36-a1b7-468f36de98ff
Elemento, Olivier
ed73e4f3-f73f-4593-996f-9dd8c42b7844
Rubin, Mark A.
1568aafa-8b43-48c9-af20-a3d150dd4891
Kimmelman, Alec C.
92ae7744-56bf-490b-83b3-5a7bea5b3dee
Pause, Arnim
e1f34ade-9c25-4647-8c61-b8d4a9405848
Cantley, Lewis C.
72b55d5f-31ed-4849-9271-60213c33f473
Emerling, Brooke M.
1e2f687f-af92-48cf-a0b5-ce968a1bcf60

Lundquist, Mark R., Goncalves, Marcus D., Loughran, Ryan M., Possik, Elite, Vijayaraghavan, Tarika, Yang, Annan, Pauli, Chantal, Ravi, Archna, Verma, Akanksha, Yang, Zhiwei, Johnson, Jared L., Wong, Jenny C.Y., Ma, Yilun, Hwang, Katie Seo Kyoung, Weinkove, David, Divecha, Nullin, Asara, John M., Elemento, Olivier, Rubin, Mark A., Kimmelman, Alec C., Pause, Arnim, Cantley, Lewis C. and Emerling, Brooke M. (2018) Phosphatidylinositol-5-phosphate 4-kinases regulate cellular lipid metabolism by facilitating autophagy. Molecular Cell, 70 (3), 531–544.e9. (doi:10.1016/j.molcel.2018.03.037).

Record type: Article

Abstract

While the majority of phosphatidylinositol-4, 5-bisphosphate (PI-4, 5-P2) in mammalian cells is generated by the conversion of phosphatidylinositol-4-phosphate (PI-4-P) to PI-4, 5-P2, a small fraction can be made by phosphorylating phosphatidylinositol-5-phosphate (PI-5-P). The physiological relevance of this second pathway is not clear. Here, we show that deletion of the genes encoding the two most active enzymes in this pathway, Pip4k2a and Pip4k2b, in the liver of mice causes a large enrichment in lipid droplets and in autophagic vesicles during fasting. These changes are due to a defect in the clearance of autophagosomes that halts autophagy and reduces the supply of nutrients salvaged through this pathway. Similar defects in autophagy are seen in nutrient-starved Pip4k2a−/−Pip4k2b−/− mouse embryonic fibroblasts and in C. elegans lacking the PI5P4K ortholog. These results suggest that this alternative pathway for PI-4, 5-P2 synthesis evolved, in part, to enhance the ability of multicellular organisms to survive starvation. Lundquist et al. reveal a critical evolutionarily conserved function of the PI5P4K family of enzymes in autophagy. PI5P4Ks generate PI-4, 5-P2 from the minor lipid PI-5-P and are required for autophagosome-lysosome fusion during metabolic stress. Importantly, this study sheds light on the anti-cancer mechanism of PI5P4K inhibition.

This record has no associated files available for download.

More information

Accepted/In Press date: 29 March 2018
e-pub ahead of print date: 3 May 2018
Published date: 3 May 2018
Keywords: autophagy, lipid kinase, lysosome, metabolism, mTORC1, phospholipid, PI5P4K, TFEB

Identifiers

Local EPrints ID: 422774
URI: http://eprints.soton.ac.uk/id/eprint/422774
ISSN: 1097-2765
PURE UUID: cf7ba1f2-6870-4de5-876f-5d37771737e5

Catalogue record

Date deposited: 03 Aug 2018 16:31
Last modified: 10 Jul 2024 20:30

Export record

Altmetrics

Contributors

Author: Mark R. Lundquist
Author: Marcus D. Goncalves
Author: Ryan M. Loughran
Author: Elite Possik
Author: Tarika Vijayaraghavan
Author: Annan Yang
Author: Chantal Pauli
Author: Archna Ravi
Author: Akanksha Verma
Author: Zhiwei Yang
Author: Jared L. Johnson
Author: Jenny C.Y. Wong
Author: Yilun Ma
Author: Katie Seo Kyoung Hwang
Author: David Weinkove
Author: Nullin Divecha
Author: John M. Asara
Author: Olivier Elemento
Author: Mark A. Rubin
Author: Alec C. Kimmelman
Author: Arnim Pause
Author: Lewis C. Cantley
Author: Brooke M. Emerling

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 http://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.

×