Work

Convergent innovation of (crypto)vivipary via asymmetric dismantling of seed desiccation and dormancy machinery

Year: 2026

Type: article

Abstract: Cryptovivipary and vivipary, referred to as (crypto)vivipary, occur across multiple angiosperm lineages and enable embryos to continue developing before dispersal. Yet, this trait raises a fundamental question: how are seed-specific abscisic acid (ABA) responses modulated to support continuous embryonic growth without compromising ABA-dependent vegetative stress tolerance? Here, integrating phylogenomic analyses of independently evolved (crypto)viviparous lineages with spatiotemporal transcriptomics and functional validation, we show that (crypto)vivipary evolved via a convergent “less-is-more” strategy rather than through novel genes or single master loci (e.g., DOG1 ). While upstream hormonal cores (e.g., ABA/GA signaling) are largely conserved, downstream seed desiccation and dormancy effectors are asymmetrically dismantled across cryptoviviparous and viviparous lineages. This remodeling, encompassing 38 shared contracted orthogroups and hundreds of lineage-specific losses, converges on eliminating the execution machinery for seed desiccation tolerance and dormancy maintenance. Consistently, orthologs of the contracted genes are enriched for dry-seed–specific expression and ABA responsiveness in non-(crypto)viviparous species. Furthermore, disrupting representative Arabidopsis orthologs (e.g., SESA1 , TIP3.2 , LEA25 , ECP63 ) recapitulates (crypto)viviparous-like phenotypes, including precocious germination, elevated seed moisture, and in most mutants, compromised storage longevity. Together, our findings demonstrate how structured contraction of terminal seed-specific modules uncouples seed developmental fate from systemic stress signaling, illuminating the molecular architecture of (crypto)vivipary.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.2602105123