Learn More
Lancelets ('amphioxus') are the modern survivors of an ancient chordate lineage, with a fossil record dating back to the Cambrian period. Here we describe the structure and gene content of the highly polymorphic approximately 520-megabase genome of the Florida lancelet Branchiostoma floridae, and analyse it in the context of chordate evolution. Whole-genome(More)
All vertebrates possess anatomical features not seen in their closest living relatives, the protochordates (tunicates and amphioxus). Some of these features depend on developmental processes or cellular behaviours that are again unique to vertebrates. We are interested in the genetic changes that may have permitted the origin of these innovations. Gene(More)
Genes of the Hox cluster are restricted to the animal kingdom and play a central role in axial patterning in divergent animal phyla. Despite its evolutionary and developmental significance, the origin of the Hox gene cluster is obscure. The consensus is that a primordial Hox cluster arose by tandem gene duplication close to animal origins. Several homeobox(More)
The amphioxus (Branchiostoma floridae) Hox cluster is a model for the ancestral vertebrate cluster, prior to the hypothesized genome-wide duplications that may have facilitated the evolution of the vertebrate body plan. Here we describe the posterior (5') genes of the amphioxus cluster, and report the isolation of four new homeobox genes. Vertebrates(More)
Organization into gene clusters is an essential and diagnostic feature of Hox genes. Insect and nematode genomes possess single Hox gene clusters (split in Drosophila); in mammals, there are 38 Hox genes in four clusters on different chromosomes. A collinear relationship between chromosomal position, activation time and anterior expression limit of(More)
Once called the 'Rosetta stone' of developmental biology, the homeobox continues to fascinate both evolutionary and developmental biologists. The birth of the homeotic, or Hox, gene cluster, and its subsequent evolution, has been crucial in mediating the major transitions in metazoan body plan. Comparative genomics studies indicate that the more recently(More)
Cephalochordates, urochordates, and vertebrates evolved from a common ancestor over 520 million years ago. To improve our understanding of chordate evolution and the origin of vertebrates, we intensively searched for particular genes, gene families, and conserved noncoding elements in the sequenced genome of the cephalochordate Branchiostoma floridae,(More)
Freshwater planarians (Platyhelminthes, Turbellaria, and Tricladida) are acoelomate, triploblastic, unsegmented, and bilaterally symmetrical organisms that are mainly known for their ample power to regenerate a complete organism from a small piece of their body. To identify potential pattern-control genes in planarian regeneration, we have isolated two(More)
The single amphioxus Hox cluster contains 15 genes and may well resemble the ancestral chordate Hox cluster. We have sequenced the Hox genomic complement of the European amphioxus Branchiostoma lanceolatum and compared it to the American species, Branchiostoma floridae, by phylogenetic footprinting to gain insights into the evolution of Hox gene regulation(More)
Hox genes are implicated in the control of axial patterning during embryonic development of many, perhaps all, animals. Here we review recent data on Hox gene diversity, genomic organization, and embryonic expression in chordates (including tunicates, amphioxus, hagfish, lampreys, teleosts) plus their putative sister group, the hemichordates. We consider(More)