Although metazoan development is conceived as resulting from gene regulatory networks (GRNs) controlled by Hox genes, a better analogy is computer architecture: i.e., a task accomplished in sequential steps linked to an external referent that " counts " each step. A developmental " step " equals the expression of genes in specific cells at specific times and telomeres represent external " count...

Sponges (Porifera) are among the simplest living and the earliest branching metazoans. They hold a pivotal role for studying genome evolution of the entire metazoan branch, both as an outgroup to Eumetazoa and as the closest branching phylum to the common ancestor of all multicellular animals (Urmetazoa). In order to assess the transcription inventory of sponges, we sequenced expressed sequence...

Formins are proteins that assist in regulating cytoskeletal organization through interactions with actin filaments and microtubules. Metazoans encode nine distinct formin subtypes based on sequence similarity, potentially allowing for great functional diversity for these proteins. Through the evolution of the eukaryotes, formins are believed to have repeatedly undergone rounds of gene duplicati...

A baffling aspect of metazoan proteostasis is the lack of an Hsp104 ortholog that rapidly disaggregates and reactivates misfolded polypeptides trapped in stress induced disordered aggregates, preamyloid oligomers, or amyloid fibrils. By contrast, in bacteria, protozoa, chromista, fungi, and plants, Hsp104 orthologs are highly conserved and confer huge selective advantages in stress tolerance. M...

SYNOPSIS. Underlying any analysis on the evolution of development is a phylogenetic framework, whether explicitly stated or implied. As such, differing views on phylogenetic relationships lead to variable interpretations of how developmental mechanisms have changed through time. Over the past decade, many long-standing hypotheses about animal evolution have been questioned causing substantial c...