Characterization of expressed sequence tags from the colonial tunicate, Botryllus schlosseri

The focus of this project was to exploit the advantages of automated sequencing technology to search in tunicates for genes with homology to vertebrate genes with known immunological relevance. A cDNA library from Botryllus schlosseri, a colonial tunicate, was used for this purpose. Partial sequences from 214 different clones from this library were obtained and compared with known sequences in GenBank. BLAST scores of {dollar}<{dollar}10{dollar}sp{lcub}-5{rcub}{dollar} were considered indicative of significant homology. Of the 214 sequences, 93 were novel (90 with open reading frames) and 121 had significant homology with other GenBank entries (24 of these were duplicate homologs).; One of the goals of this project was to identify B. schlosseri sequences that might be relevant to internal defense and that could yield insights into the evolution of immunity in the chordates. Four B. schlosseri ESTs with significant BLAST scores to molecules known to function in internal defense were singled out for further sequence analysis: P-selectins/Von Willebrand's Factor; properdin; fibrinogen; and valosin containing protein. (Abstract shortened by UMI.)...