Evidence against tetrapod-wide digit identities and for a limited frame shift in bird wings.

ABSTRACT: In crown group tetrapods, individual digits are homologized in relation to a pentadactyl ground plan. However, testing hypotheses of digit homology is challenging because it is unclear whether digits represent distinct and conserved gene regulatory states. Here we show dramatic evolutionary dynamism in the gene expression profiles of digits, challenging the notion that five digits have conserved developmental identities across amniotes. Transcriptomics shows diversity in the patterns of gene expression differentiation of digits, although the anterior-most digit of the pentadactyl limb has a unique, conserved expression profile. Further, we identify a core set of transcription factors that are differentially expressed among the digits of amniote limbs; their spatial expression domains, howe

SUBMITTER: Stewart TA 

PROVIDER: S-EPMC6642197 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature