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bioRxiv · 10.1101/2020.03.20.000075

Biochemical paedomorphosis and genetic assimilation in the hypoxia adaptation of Tibetan antelope

Storz, J. F.·Signore, A. V.
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Abstract

Developmental shifts in stage-specific gene expression can provide a ready mechanism of phenotypic change by altering the rate or timing of ontogenetic events. We discovered that the high-altitude Tibetan antelope (Panthelops hodgsonii) has evolved an adaptive increase in blood-O2 affinity by truncating the ancestral ontogeny of globin gene expression such that a high-affinity juvenile hemoglobin isoform (isoHb) completely supplants the lower-affinity isoHb that is expressed in the adult red blood cells of other bovids. This juvenilization of blood properties represents a canalization of an acclimatization response to hypoxia that has been well-documented in adult goats and sheep. We also discovered the genomic mechanism underlying this regulatory isoHb switch, revealing how a reversible acclimatization response became genetically assimilated as an irreversible adaptation to chronic hypoxia.

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Storz, J. F., Signore, A. V.. 2020-03-22. Biochemical paedomorphosis and genetic assimilation in the hypoxia adaptation of Tibetan antelope. https://doi.org/10.1101/2020.03.20.000075

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