The vacuolar-ATPase complex and assembly factors, TMEM199 and CCDC115, control HIF1α prolyl hydroxylation by regulating cellular iron levels

Hypoxia Inducible transcription Factors (HIFs) are principally regulated by the 2-oxoglutarate and Iron(II) prolyl hydroxylase (PHD) enzymes, which hydroxylate the HIFα subunit, facilitating its proteasome-mediated degradation. Observations that HIFα hydroxylation can be impaired even when oxygen is sufficient emphasise the importance of understanding the complex nature of PHD regulation. Here, we use an unbiased genome-wide genetic screen in near-haploid human cells to uncover cellular processes that regulate HIF1α. We identify that genetic disruption of the Vacuolar H+ ATPase (V-ATPase), the key proton pump for endo-lysosomal acidification, and two previously uncharacterised V-ATPase assembly factors, TMEM199 and CCDC115, stabilise HIF1α in aerobic conditions. Rather than preventing the lysosomal degradation of HIF1α, disrupting the V-ATPase results in intracellular iron depletion, thereby impairing PHD activity and leading to HIF activation. Iron supplementation directly restores PHD catalytic activity following V-ATPase inhibition, revealing important links between the V-ATPase, iron metabolism and HIFs.

Medienart:

E-Artikel

Erscheinungsjahr:

2017

Erschienen:

2017

Enthalten in:

Zur Gesamtaufnahme - volume:6

Enthalten in:

eLife - 6(2017) vom: 15. März

Sprache:

Englisch

Beteiligte Personen:

Miles, Anna L [VerfasserIn]
Burr, Stephen P [VerfasserIn]
Grice, Guinevere L [VerfasserIn]
Nathan, James A [VerfasserIn]

Links:

Volltext

Themen:

Biochemistry
CCDC115
Ccdc115 protein, human
Cell biology
E1UOL152H7
EC 1.14.11.-
EC 3.6.1.-
Ferritinophagy
HIF
HIF1A protein, human
Human
Hypoxia Inducible factors
Hypoxia-Inducible Factor 1, alpha Subunit
Iron
Journal Article
Membrane Proteins
Nerve Tissue Proteins
PHD
Prolyl Hydroxylases
Prolyl hydroxylation
Research Support, Non-U.S. Gov't
TMEM199
TMEM199 protein, human
Transferrin
VATPase
Vacuolar ATPase
Vacuolar Proton-Translocating ATPases
Vma12
Vma22

Anmerkungen:

Date Completed 02.05.2017

Date Revised 13.11.2018

published: Electronic

Citation Status MEDLINE

doi:

10.7554/eLife.22693

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM269870563