Divergent acyl carrier protein decouples mitochondrial Fe-S cluster biogenesis from fatty acid synthesis in malaria parasites

  1. Seyi Falekun
  2. Jaime Sepulveda
  3. Yasaman Jami-Alahmadi
  4. Hahnbeom Park
  5. James A Wohlschlegel
  6. Paul A Sigala  Is a corresponding author
  1. University of Utah School of Medicine, United States
  2. University of California, Los Angeles, United States
  3. University of Washington, United States

Abstract

Most eukaryotic cells retain a mitochondrial fatty acid synthesis (FASII) pathway whose acyl carrier protein (mACP) and 4-phosphopantetheine (Ppant) prosthetic group provide a soluble scaffold for acyl chain synthesis and biochemically couple FASII activity to mitochondrial electron transport chain (ETC) assembly and Fe-S cluster biogenesis. In contrast, the mitochondrion of Plasmodium falciparum malaria parasites lacks FASII enzymes yet curiously retains a divergent mACP lacking a Ppant group. We report that ligand-dependent knockdown of mACP is lethal to parasites, indicating an essential FASII-independent function. Decyl-ubiquinone rescues parasites temporarily from death, suggesting a dominant dysfunction of the mitochondrial ETC. Biochemical studies reveal that Plasmodium mACP binds and stabilizes the Isd11-Nfs1 complex required for Fe-S cluster biosynthesis, despite lacking the Ppant group required for this association in other eukaryotes, and knockdown of parasite mACP causes loss of Nfs1 and the Rieske Fe-S protein in ETC Complex III. This work reveals that Plasmodium parasites have evolved to decouple mitochondrial Fe-S cluster biogenesis from FASII activity, and this adaptation is a shared metabolic feature of other apicomplexan pathogens, including Toxoplasma and Babesia. This discovery unveils an evolutionary driving force to retain interaction of mitochondrial Fe-S cluster biogenesis with ACP independent of its eponymous function in FASII.

Data availability

All data reported or analyzed in this manuscript are available and included in the main and supplemental figures and in the source data files.

Article and author information

Author details

  1. Seyi Falekun

    University of Utah School of Medicine, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jaime Sepulveda

    University of Utah School of Medicine, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Yasaman Jami-Alahmadi

    University of California, Los Angeles, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Hahnbeom Park

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. James A Wohlschlegel

    University of California, Los Angeles, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Paul A Sigala

    University of Utah School of Medicine, Salt Lake City, United States
    For correspondence
    p.sigala@biochem.utah.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3464-3042

Funding

National Institute of General Medical Sciences (R35GM133764)

  • Paul A Sigala

National Institute of General Medical Sciences (R01GM089778)

  • James A Wohlschlegel

National Institute of Diabetes and Digestive and Kidney Diseases (U54DK110858)

  • Paul A Sigala

Burroughs Wellcome Fund (1011969)

  • Paul A Sigala

Pew Charitable Trusts (32099)

  • Paul A Sigala

National Institute of General Medical Sciences (T32GM122740)

  • Jaime Sepulveda

National Institutes of Health (S10OD018210)

  • Paul A Sigala

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Malcolm J McConville, The University of Melbourne, Australia

Publication history

  1. Preprint posted: April 13, 2021 (view preprint)
  2. Received: June 25, 2021
  3. Accepted: October 6, 2021
  4. Accepted Manuscript published: October 6, 2021 (version 1)
  5. Version of Record published: October 26, 2021 (version 2)

Copyright

© 2021, Falekun et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 1,204
    Page views
  • 189
    Downloads
  • 0
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Seyi Falekun
  2. Jaime Sepulveda
  3. Yasaman Jami-Alahmadi
  4. Hahnbeom Park
  5. James A Wohlschlegel
  6. Paul A Sigala
(2021)
Divergent acyl carrier protein decouples mitochondrial Fe-S cluster biogenesis from fatty acid synthesis in malaria parasites
eLife 10:e71636.
https://doi.org/10.7554/eLife.71636

Further reading

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Morgan L Pimm et al.
    Research Article Updated

    Profilin-1 (PFN1) is a cytoskeletal protein that regulates the dynamics of actin and microtubule assembly. Thus, PFN1 is essential for the normal division, motility, and morphology of cells. Unfortunately, conventional fusion and direct labeling strategies compromise different facets of PFN1 function. As a consequence, the only methods used to determine known PFN1 functions have been indirect and often deduced in cell-free biochemical assays. We engineered and characterized two genetically encoded versions of tagged PFN1 that behave identical to each other and the tag-free protein. In biochemical assays purified proteins bind to phosphoinositide lipids, catalyze nucleotide exchange on actin monomers, stimulate formin-mediated actin filament assembly, and bound tubulin dimers (kD = 1.89 µM) to impact microtubule dynamics. In PFN1-deficient mammalian cells, Halo-PFN1 or mApple-PFN1 (mAp-PEN1) restored morphological and cytoskeletal functions. Titrations of self-labeling Halo-ligands were used to visualize molecules of PFN1. This approach combined with specific function-disrupting point-mutants (Y6D and R88E) revealed PFN1 bound to microtubules in live cells. Cells expressing the ALS-associated G118V disease variant did not associate with actin filaments or microtubules. Thus, these tagged PFN1s are reliable tools for studying the dynamic interactions of PFN1 with actin or microtubules in vitro as well as in important cell processes or disease-states.

    1. Biochemistry and Chemical Biology
    2. Structural Biology and Molecular Biophysics
    Brandon Wey-Hung Liauw et al.
    Research Article

    Activation of G protein-coupled receptors (GPCRs) is an allosteric process. It involves conformational coupling between the orthosteric ligand binding site and the G protein binding site. Factors that bind at non-cognate ligand binding sites to alter the allosteric activation process are classified as allosteric modulators and represent a promising class of therapeutics with distinct modes of binding and action. For many receptors, how modulation of signaling is represented at the structural level is unclear. Here, we developed FRET sensors to quantify receptor modulation at each of the three structural domains of metabotropic glutamate receptor 2 (mGluR2). We identified the conformational fingerprint for several allosteric modulators in live cells. This approach enabled us to derive a receptor-centric representation of allosteric modulation and to correlate structural modulation to the standard signaling modulation metrics. Single-molecule FRET analysis revealed that a NAM increases the occupancy of one of the intermediate states while a PAM increases the occupancy of the active state. Moreover, we found that the effect of allosteric modulators on the receptor dynamics is complex and depend on the orthosteric ligand. Collectively, our findings provide a structural mechanism of allosteric modulation in mGluR2 and suggest possible strategies for design of future modulators.