RRC ID 446
Author Imamura M, Yamakawa M.
Title Molecular cloning and expression of a Toll receptor gene homologue from the silkworm, Bombyx mori.
Journal Biochim. Biophys. Acta
Abstract A novel Toll receptor gene was cloned from the bacterial artificial chromosomal (BAC) library of the silkworm, Bombyx mori, using primers for polymerase chain reactions (PCR), synthesized based on an expressed-sequence tag (EST). The open reading frame of this gene was intronless. The deduced amino acid sequence including a putative signal peptide from the nucleotide sequence of the B. mori Toll (BmToll) gene shows 53.7%, 49.0%, 42.3% and 39.2% similarity to those of Toll-7, 18 wheeler (18w), Toll-6 and Toll-8 from Drosophila melanogaster. BmToll, however, does not show marked similarity to Toll, Toll-3, Toll-4 or Toll-5. Phylogenetic insect Toll family analysis shows that BmToll is strongly related to Toll-7 and 18w. An analysis of the tissue-specific expression of the BmToll gene by reverse transcription PCR (RT-PCR) showed that the BmToll gene is constitutively expressed in the fat body but not in the Malpighian tubule, silk gland, midgut or hemocyte. Injecting lipopolysaccharide (LPS) into silkworm hemocoel strongly suppressed BmToll gene expression. The time course showed that BmToll gene expression is totally suppressed within 2 h and gene transcripts appeared again 12 h after LPS injection, suggesting strong downregulation of the BmToll gene expression by LPS.
Volume 1576(3)
Pages 246-54
Published 2002-7-19
PII S0167478102003366
PMID 12084571
MeSH Amino Acid Sequence Animals Base Sequence Bombyx / genetics* Bombyx / metabolism* Cloning, Molecular Drosophila Proteins* Gene Expression Regulation Insect Proteins / chemistry Insect Proteins / classification Insect Proteins / genetics* Insect Proteins / metabolism Membrane Glycoproteins / chemistry Membrane Glycoproteins / classification Membrane Glycoproteins / genetics* Membrane Glycoproteins / metabolism Molecular Sequence Data Phylogeny Receptors, Cell Surface / chemistry Receptors, Cell Surface / classification Receptors, Cell Surface / genetics* Receptors, Cell Surface / metabolism Sequence Alignment Tissue Distribution Toll-Like Receptors
IF 3.79
Times Cited 16
Silkworms EST database p50