Comparative analysis of mitochondrial proteomes across the tree of life

Original title: Comparative analysis of mitochondrial proteomes across the tree of life.

Mitochondria arose from the endosymbiosis of a bacterium with an archaea-related host cell about 2 billion years ago.

By Chen, Stefely, Bardon +3CellOct 1, 2026

Score█████░░░░░4.8

Key numbers

43% lack Pfam domains

VerdictCompetent work. Briefs at most.

Read the original

Abstract

Mitochondria arose from the endosymbiosis of a bacterium with an archaea-related host cell about 2 billion years ago. To understand their origins and evolution, we compared experimentally defined mitoproteomes from the MitoCarta Tree of Life project. Across eight organisms, we identified 8,619 distinct mitochondrial proteins within 3,199 families, of which 43% lack Pfam domains. We report 33 protein families conserved in eukaryotic pathogens yet absent in humans, representing promising candidate targets for protozoan infectious diseases. Leveraging our experimentally defined mitoproteomes, we retrained a classifier based on a protein language model to predict mitoproteomes of ∼200 eukaryotes. From this expanded set, we detail the evolutionary trajectories of mitochondria, ranging from clade-specific gene family expansions to extreme mitoproteome reductions seemingly en route to complete organelle loss. Finally, we reconstruct the last eukaryotic common ancestor (LECA) mitoproteome, revealing that LECA possessed a complex mitochondrion capable of both aerobic and anaerobic metabolism.

Michael Z Chen, Jonathan A Stefely, Eric G Bardon, MitoCarta Tree of Life Consortium, Sarah E Calvo, Vamsi K Mootha

The editor's rubric

Heuristic review

Dimension	Level	Weight	What that level means
Leverage	███░░ 3	24%	A method or resource many groups across the field will adopt within a year.
Magnitude	██░░░ 2	16%	Solid incremental gain on a meaningful problem.
Evidence	███░░ 3	20%	Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.
Novelty	██░░░ 2	20%	A new combination of known ideas.
Trajectory	██░░░ 2	10%	Some room to improve with obvious engineering.
Stakes	██░░░ 2	10%	Benefits a professional community (practitioners, clinicians, engineers).

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: method (we report); breadth (many tasks). Red flags: derivative (comparative study).

How the score was computed

rank-2026-09-29

Score█████░░░░░4.8

Score = 10 × (75% × adjusted merit / 10 + 15% × attention + 10% × freshness)

Merit: 4.9 / 10; Weighted rubric, evidence-gated.
Adjusted merit: 4.3 / 10; Shrunk toward the desk prior by editor confidence (34%).
Attention: 54%; Citations, upvotes, points, mentions.
Freshness: 80%; Half-life decay since publication.

Citations7 (reference 20, via openalex, Oct 3, 2026, 05:48 UTC)
Field-weighted citation impact16.7 (reference 3, via openalex, Oct 3, 2026, 05:48 UTC)

The record

Reviewed by heuristic-v2 on Oct 3, 2026, 05:48 UTC. Paper type: method.
Categories: Comparative Study, Journal Article, Mitochondria, Animals, Humans, Mitochondrial Proteins, Proteome, Evolution, Molecular, Phylogeny, Eukaryota
LEAD, No.1 in the Biology edition of October 3, 2026.