Annelid functional genomics reveal the origins of bilaterian life cycles.

ABSTRACT: Indirect development with an intermediate larva exists in all major animal lineages¹, which makes larvae central to most scenarios of animal evolution^2-11. Yet how larvae evolved remains disputed. Here we show that temporal shifts (that is, heterochronies) in trunk formation underpin the diversification of larvae and bilaterian life cycles. We performed chromosome-scale genome sequencing in the annelid Owenia fusiformis with transcriptomic and epigenomic profiling during the life cycles of this and two other annelids. We found that trunk development is deferred to pre-metamorphic stages in the feeding larva of O. fusiformis but starts after gastrulation in the non-feeding larva with gradual metamorphosis of Capitella teleta and the direct developing embryo of Dimorphi

SUBMITTER: Martin-Zamora FM 

PROVIDER: S-EPMC9977687 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature