The hourglass and the early conservation models--co-existing patterns of developmental constraints in vertebrates.

ABSTRACT: Developmental constraints have been postulated to limit the space of feasible phenotypes and thus shape animal evolution. These constraints have been suggested to be the strongest during either early or mid-embryogenesis, which corresponds to the early conservation model or the hourglass model, respectively. Conflicting results have been reported, but in recent studies of animal transcriptomes the hourglass model has been favored. Studies usually report descriptive statistics calculated for all genes over all developmental time points. This introduces dependencies between the sets of compared genes and may lead to biased results. Here we overcome this problem using an alternative modular analysis. We used the Iterative Signature Algorithm to identify distinct modules of genes co-expressed

SUBMITTER: Piasecka B 

PROVIDER: S-EPMC3636041 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature