ABSTRACT
Hormonal processes along with enzymatic processing similar to that found in vertebrates occur in annelids. Amino acid sequence determination of annelids precursor gene products reveals the presence of the respective peptides that exhibit high sequence identity to their mammalian counterparts. Annelids and Molluscs are both lophochotrozoans, and in this context, several families of peptides have been well conserved in these two groups as reflected by the genomes screening. The history of neurobiology demonstrates the significance of the invertebrate nervous system as a valuable model. The giant axon of the squid and crayfish neuromuscular junction stands out in this regard. Analysis of the Hirudo transcriptome database reveals the presence of putative homologs of all the factors reported to play critical roles in human Toll-like receptor pathways.
