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bioRxivSource publication:

A 396-node human cell-lineage tree test finds anatomical compartment identity explains about 75% of metabolic-tier variance while lineage depth explains almost none

Synopsis

Using a curated 396-node human cell-lineage tree spanning the zygote to terminal somatic identities, the study tested whether organ-level standard metabolic rate (SMR) is better predicted by developmental time (lineage depth) or by terminal fate identity (anatomical compartment), finding that lineage depth explains essentially none of the variance in a cell's metabolic tier (r = 0.11, R2 approximately 1.2%) whereas compartment identity explains roughly 75%, and that the mean mitochondrial volume fraction of an organ's constituent terminal cell types tracks literature-derived organ SMR with r = 0.90 across five canonical reference-man organ groups, motivating a five-layer computable framework and a metabolic commitment-horizon model.

Source-provided article image: The Metabolic Organ Clock: A Computable Framework Linking Cell-Lineage Architecture to Emergent Organ Bioenergetics
Figure 1 ·

Figure 1. The five-layer computable framework proposed in this paper, instantiated with the quantitative results reported in

bioRxiv · Page 4

Interpretation

The work proposes and tests a computable framework linking cell-lineage tree topology to adult organ bioenergetics, with five layers: lineage as a formal tree grammar, information-theoretic structure of the tree, metabolic switches as runtime operators, compilation to organ-level energetic networks, and execution as organism-level bioenergetics. Cell-type atlases already annotate mitochondrial abundance, dominant fuel pathway, and lineage of origin, but no computable model connected lineage-tree topology to adult organ metabolic rate; this work supplies an explicit five-layer framework for that connection. Based on a curated 396-node human cell-lineage tree spanning the zygote to terminal somatic identities; the framework is motivated by the reported statistical results.

For predicting a cell's metabolic tier, anatomical compartment identity is far more explanatory than developmental time: lineage depth explains essentially none of the variance (r = 0.11, R2 approximately 1.2%), while compartment identity explains roughly 75%. This directly contrasts two candidate explanations, developmental time versus terminal fate identity, and quantifies compartment identity as dominant rather than leaving it qualitative. Regression analysis on the 396-node lineage tree, reporting correlation and R2.

The mean mitochondrial volume fraction of an organ's constituent terminal cell types is highly correlated with that organ's classical literature-derived SMR, with r = 0.90 across five canonical reference-man organ groups. It links cell-level mitochondrial abundance to the classical physiological SMR measure at organ level, providing an empirical basis for cross-scale inference. Between-group correlation across five canonical reference-man organ groups, r = 0.90.

The study introduces the metabolic commitment-horizon model, the hypothesis that a cell's metabolic tier is fixed at a discrete lineage-commitment event and thereafter held constant rather than accumulated continuously with differentiation time; in 5-fold cross-validation (n = 396), a nearest-commitment-ancestor predictor beat a global-mean null (MAE 0.752 vs 0.809, p = 0.015) but was not significantly better than a lineage-depth regression (delta MAE = -0.042, 95% CI -0.098 to +0.012, p = 0.175), so the model is reported as descriptively supported but not yet discriminated predictively. It frames metabolic-tier formation as a testable discrete-commitment hypothesis and explicitly reports that its predictive power is not yet distinguished from a lineage-depth regression. 5-fold cross-validation, n = 396; significant versus the null, not significant versus the lineage-depth regression.

Perspective

The result is aimed at researchers studying human cell lineages and organ energetics, and applies to modeling settings that take a curated lineage tree and literature-derived SMR as inputs; it treats insulin resistance as an acquired perturbation of the clock and closes with eight testable predictions and falsification conditions, offering a starting point for extending the framework on primary single-cell data and for connecting this within-species result to the classical cross-species rate-of-living hypothesis.

The predictive difference between the commitment-horizon model and the lineage-depth regression was not significant (delta MAE = -0.042, 95% CI -0.098 to +0.012, p = 0.175), so the mechanistic hypothesis is currently only descriptively supported; the correlation between mitochondrial volume fraction and SMR rests on five reference organ groups, a limited number of groups; moreover this reading scope is incomplete, lacking the main text, figures, and supplementary materials, so the lineage-tree construction details, the definition of metabolic tier, and the specific cross-validation implementation cannot be checked, which are open questions a reader should keep in mind.

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