José Díaz Maldonado

Mitochondria contact lipid droplets through the mitochondrial import complex binding to lipid metabolism enzyme Ayr1 - Nature Cell Biology Heinen et al. show that the mitochondrial import complex recruits lipid droplets to the mitochondrial outer membrane. The mitochondrial import complex binds to the lipid metabolism enzyme Ayr1 and con...

Mitochondria contact lipid droplets through the mitochondrial import complex binding to lipid metabolism enzyme Ayr1
www.nature.com/articles/s41...

Metabolic stress reveals widespread accumulation of cap-unmethylated RNAs https://www.biorxiv.org/content/10.64898/2026.02.23.707474v1

Mammalian cells form hibernating disomes akin to those in bacterial cells - but connected via ribosomal RNA

www.science.org/doi/10.1126/...

co-first with: @andschwarz.bsky.social

with: @lea-dietrich.bsky.social, @sgiando.bsky.social, @erin-schuman.bsky.social and many more

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#MolBio 🧪

Eukaryogenesis in light of an expanded catalogue of Asgard genomes. a, Simplified, scaled timeline spanning from before the Last Asgard archaea Common Ancestor (LAsCA) to today. Thin bands mark predicted time ranges of relevant events (for example, GOE), thicker bands represent processes (for example, eukaryogenesis), and brackets indicate the period shown in b. The timeline further highlights milestones, including potential early eukaryotic fossils60 and the modern-day co-occurrence of Heimdallarchaeia and Alphaproteobacteria observed in this study (interaction likely originated earlier).

Fig. 1 | Expanded genomic diversity of Asgard archaea. a, Maximum-likelihood phylogeny based on 47 non-ribosomal markers (NM47)using the WAG + C10 + R4 model with 100 nonparametric bootstrap pseudoreplicates, including 869 Asgardarchaeota MAGs and 309 outgroup genomes. The blue branches (lower right) indicate the new Asgardarchaeota classes, Ranarchaeia, and the recently proposed Asgardarchaeia4. The concentric rings denote (in to out): the predicted genome size, metabolic guilds based on Pfam clustering, sampling locations, and black stars on the outside mark MAGs added by this study. Asgard, Asgardarchaeia; Atabey, Atabeyarchaeia; Baldr, Baldrarchaeia; Frey/Jord, Frey/Jordarchaeia; Gerd, Gerdarchaeales; Heimdall, Heimdallarchaeaceae; Hel, Helarchaeales; Hermod, Hermodarchaeia; Hod, Hodarchaeales; Kari, Kariarchaeaceae; Loki, Lokiarchaeales; Njord, Njordarchaeales; Odin, Odinarchaeia; Ran, Ranarchaeia; Sif, Sifarchaeia; Thor, Thorarchaeia; Wukong, Wukongarchaeia. b, SR4-recoded phylogeny of the same genome set inferred with the model GTR + C60 + G and 100 nonparametric bootstrap pseudoreplicates (Methods). This updated catalogue constitutes a large increase in the medium- to high-quality publicly available genomes (completeness >50% and contamination and redundancy <10%) with 65.3% from the Guaymas Basin and 34.7% from the Bohai Sea. The encircled numbers represent MAGS added by this study. The scale bars in bothsubpanels represent the average number of substitutions per site.Map created in BioRender; Appler, K. https://biorender.com/147ieoc(2025).

Our work is published today: ‘Oxygen metabolism in descendants of the archaeal-eukaryotic ancestor’. This was a huge effort lead by @katyappler.bsky.social. Extremely grateful to have been a part of this amazing project! 😊🦠🧬

Links: www.nature.com/articles/s41...
www.nature.com/articles/s41...

Cytoplasmic mRNA granules regulate cell fate decisions during PINK1/Parkin mitophagy https://www.biorxiv.org/content/10.64898/2026.02.13.705862v1

Mechanisms and disease relevance of mitochondrial translation in humans Nature Reviews Molecular Cell Biology, Published online: 13 February 2026; doi:10.1038/s41580-026-00948-2This Review discusses new insights into the intricate regulation of mitochondrial protein synthesis, the pathological consequences of its dysfunction in cancer and immunity, and the complexity of therapeutic targeting of mitochondrial translation.

New Online! Mechanisms and disease relevance of mitochondrial translation in humans

Organelle communication networks rewire to support lipid metabolism during neuronal differentiation https://www.biorxiv.org/content/10.64898/2026.02.10.704675v1

Graphical abstract

Researchers identify brain neurons responsible for building endurance after exercise #inmice. spkl.io/63322AtDPj

J. Nicholas Betley & colleagues
@cp-neuron.bsky.social

Long in the making, but happy to present the Chlamydomonas chlororibosome!
Cryo-ET🔬reveals a large new domain on the small subunit, built from multiple extensions in conserved ribosomal proteins.
bioRxiv 📖: shorturl.at/q44tG
This suggests greater chlororibosome diversity than expected!
1/n 🧵

Live-cell single-molecule dynamics of eukaryotic RNA polymerase machineries Eukaryotic gene expression is orchestrated by RNA polymerases (RNAPI, II, and III) and associated factors, yet their real-time dynamics remain obscure. Using single-molecule tracking in living yeast, ...

🧬🔬🎥 @science.org Live-cell single-molecule dynamics of eukaryotic RNA polymerase machineries | Science www.science.org/doi/10.1126/...

Integrative modelling reveals the structure of the human Mic60-Mic19 subcomplex and its role as a diffusion barrier in mitochondria.

www.biorxiv.org/content/10.6...

ALKB-1-dependent tRNA methylation is required for efficient paternal mitochondrial elimination

www.nature.com/articles/s41...

Schwarz lab @bostonchildrens.bsky.social identify a mechanism coupling mitochondrial movement to energy demand. When energy levels are low, the energy-sensing kinase AMPK phosphorylates the motor/adaptor protein TRAK1, arresting #mitochondria via the #actin #cytoskeleton. rupress.org/jcb/article/...

5' UTR length regulates alternative N-terminal protein isoform production in health and disease https://www.biorxiv.org/content/10.64898/2026.01.20.700518v1

We then used qExM to measure the abundance of mitochondrial respiratory chain complexes in situ!

We measured the abundances for Complex I, III, and IV.

How they differ in absolute abundances in metabolically distinct subpopulations

And even how T-cell activation changes supercomplex density

For ~century, we’ve asked: why do proliferating cells ferment glucose even when O2 is around? I’m thrilled to share our latest work @natmetabolism.nature.com, led by @thebiokimist.bsky.social. By leveraging conditional essentiality in HPLM, we propose a provocative new answer to this classic Q. 🧵

Neat RNA papers

www.nature.com/articles/s41...
(polyamine regulation of splicing by direct binding to U2 snRNP proteins)
and
www.nature.com/articles/s41...
(impact of N1-methyl pseudo U on translation)

A genetically encoded device for transcriptome storage in mammalian cells Understanding how cells make decisions over time requires the ability to link past molecular states to future phenotypic outcomes. We present TimeVault, a genetically encoded system that records and s...

🧬🔬@science.org A genetically encoded device for #transcriptome storage in mammalian cells | Science www.science.org/doi/10.1126/... @broadinstitute.org

A dynamic displacement mechanism drives protein import into mitochondria Most mitochondrial proteins are produced in the cytosol and imported through the translocase of the outer mitochondrial membrane (TOM) to reach their final destination. Although this protein entry gat...

📢 New preprint alert!
How do proteins enter mitochondria? We uncovered a surprising mechanism at the mitochondrial entry gate—using #NMR, in vivo single-particle tracking, yeast experiments, and MD simulations to crack the code.
www.biorxiv.org/content/10.6...
#StructuralBiology #Mitochondria
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Graphical abstract on LipoID workflow

LipoID profiles lipid droplet interactions and identifies interorganelle regulators

www.nature.com/articles/s41...

Mitochondrial hitch-hiking of Mapt mRNA maintains Tau levels in axons https://www.biorxiv.org/content/10.64898/2026.01.09.698691v1

The transcription of a single olfactory receptor per neuron is enforced by epigenetic silencing of their enhancers https://www.biorxiv.org/content/10.64898/2025.12.22.695993v1

Final version is out! Our large-scale cryo-ET dataset 🔬 of Chlamydomonas reinhardtii 🦠 is now published in @cp-molcell.bsky.social

Huge collaborative effort! So glad to see the community already using it to develop new resources & tools.

Check it out here: shorturl.at/z4i4c
#CryoEM #CryoET

Self-renewal of neuronal mitochondria through asymmetric division https://www.biorxiv.org/content/10.64898/2025.12.17.694973v1

Organelles do NOT have a single uniform pH.
And if you think they must, because “protons diffuse fast,” this paper is for you.
A thread on why that assumption is wrong; and what we found instead. 🧵 1/n

Towards CRISPR-based editing of the mitochondrial genome in yeast Mitochondria, which evolved from symbiotic bacteria, possess their own genomes (mtDNA) and support independent transcription and translation within the organelle. Given the essential role of mtDNA in ...

New work describes our efforts to achieve CRISPR editing of the mitochondrial genome.

www.biorxiv.org/lookup/conte...

Mutations in mitochondrial ferredoxin FDX2 suppress frataxin deficiency - Nature A forward genetic screen in Caenorhabditis elegans reveals that decreased levels of the&nbsp;ferredoxin FDX2 suppress&nbsp;the loss of frataxin in worms and in mice by relief of FDX2 inhibition of fra...

www.nature.com/articles/s41...

Neuronal fatty acid oxidation fuels memory after intensive learning in Drosophila - Nature Metabolism Neurons are shown to use fatty acid β-oxidation as a fuel source for memory formation upon intensive learning in Drosophila, challenging the view that neurons are unable to use fatty acids for energy ...

Neuronal fatty acid oxidation fuels memory after intensive learning in Drosophila

doi.org/10.1038/s422...

Oxidative phosphorylation complexes contain subunits encoded by both the nuclear and mitochondrial genomes. How do cells coordinate the synthesis and assembly of these complexes at the inner membrane? We teamed up with Martin Ott (@mitolab.bsky.social) to address this in two recent papers.

Mitochondrial pull-out controls mitochondrial structure in response to mitochondrial activity https://www.biorxiv.org/content/10.1101/2025.11.25.690431v1