The NK cluster in the last common ancestor to protostomes
and deuterostomes probably contained a cluster of nine NK genes: Msx, NKl/slouch, NK3/bagpipe, NK4/tinman, Tlx/cl5, NK7, NK6/hgtx, NK5/Hmx, and Lbxl ladybird genes (Holland 2001, Garcia-Fernandez 2005, Larroux et al.
chordates and echinoderms) rather than protostomes
The cells that make up the primary ciliated band are also much smaller than those of other protostomes
, as is expected if they undergo continued division.
It is also important to note that, due to high sequence conservation, the polyclonal Hb-like antibody is not likely to distinguish multiple copies of Hb in protostome
genomes; therefore the molluscan proteins are referred to as Hb-like homologs.
) using human genes implicated in wound healing in the initial query Extracellular matrix ID Protostome
E proteins hit value Human query SLRPs (small leucine-rich-repeal proteins) Biglycan AAA52287 XM_001649763 3e-21 Chondroadherin AAK51556 XM_970227 3e-26 Decorin AAB60901 No match n/a Fibrinidulin CAA53233 AJ549813 9e-21 Keratocan NP_008966 XM_001650288 8e-16 Lumican AAA91639 XM_395331 3e-17 Opticin CAB53459 XM_001606218 4e-11 Osteoglyein CAI16695 NM_206253 4e-04 PRELP CAG47066 XM_001360484 2e-15 Other extraceluar matrix proteins Asporin CAI16697 XM_967172 2e-28 Dermatan Sulf.
The first is a relatively small group with structural similarity and TIR domain sequence that ally them with most of the protostome
Finally, we examined representative metazoan genomes and found highly conserved usherin genes throughout the deuterostome lineage as well as in some protostomes
So the main question is this: Are the trochophora and dipleurula larvae ancestral to protostomes
and deuterostomes (or perhaps ambulacrarians), respectively, or have these larval types evolved convergently in several clades?
Sexual maturation was shunted to the terminal benthic stage, but the swimming, feeding trochophore and dipleurula were retained as the larval form of protostomes
and deuterostomes, respectively.
18S rRNA suggests that Entoprocta are protostomes
, unrelated to Ectoprocta.
kowalevskii are the ecdysozoan protostomes
, Drosophila (2.
Funding for this project was provided by the Monterey Bay Aquarium Research Institute (The David and Lucile Packard Foundation), NSF Award #0334932 (under the Assembling the Tree of Life program) to investigate the Tree of Life for Protostomes
, and SIO startup funds to GWR.