Cloning of chitinase-like protein1 cDNA from dicyemid mesozoans (Phylum: Dicyemida).
Dicyemid mesozoans are endoparasites found in the renal sacs of benthic cephalopods. Adult dicyemids insert the distinct anterior region, termed a "calotte," into renal tubules of the host. We cloned cDNA encoding chitinase-like protein from the dicyemid Dicyema japonicum (Dicyema-clp 1), and also cloned the gene fragment corresponding to the cDNA. Dicyema-clp1 has the hydrophobic amino acid-rich region, but not the chitin-binding domains at the C terminus. Analyses using the SignalP prediction program suggest this hydrophobic amino acid-rich region is the anchor sequence to plasma membranes. The putative catalytic site in glyco18 domain exhibited 1 substitution from aspartic acid to asparagine. The gene fragment had short 9 introns (22-26 bp), and the coding sequence consisted of 10 exons (30-233 bp). Specific and strong expression of Dicyema-clpl was detected in the calotte of vermiform stages by whole mount in situ hybridization. N-acetyl-D-glucosamine was detected on the outer surface of both peripheral cells of dicyemids and epidermal cells of host renal appendages. Dicyema-clp appears to be associated with N-acetyl-D-glucosamine in the interface between dicyemid peripheral cells and epidermal cells of the host renal appendage, and possibly aids in adhering the calotte to host epidermal cells.
Ogino
Kazutoyo
K
Department of Biology, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan. ogino@bio.sci.osaka-u.ac.jp
Tsuneki
Kazuhiko
K
Furuya
Hidetaka
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D049830:Cephalopoda / Q000469:parasitology*; D002688:Chitinases / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics*; D005091:Exons; D015971:Gene Expression Regulation, Enzymologic; D007438:Introns; D007448:Invertebrates / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D010271:Parasites / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D010802:Phylogeny; D013559:Symbiosis
D018076:DNA, Complementary; D002688:Chitinases