Analysis of the insect os-d-like gene family.
Insect OS-D-like proteins, also known as chemosensory (CSP) or sensory appendage proteins (SAP), are broadly expressed in various insect tissues, where they are thought to bind short to medium chain length fatty acids and their derivatives. Although their specific function remains uncertain, OS-D-like members have been isolated from sensory organs (including the sensillum lymph in some cases), and a role in olfaction similar to that of the insect odorant binding proteins (OBP) has been suggested for some. We have identified 15 new OS-D-like sequences: four from cDNA clones described herein and 11 from sequence databases. The os-d-like genes from the Anopheles gambiae, Apis mellifera, Drosophila melanogaster, and Drosophila pseudoobscura genomes typically have single, small introns with a conserved splice site. Together with all family members entered on GenBank, a total of 70 OS-D-like proteins, representing the insect orders Diptera, Dictyoptera, Hymenoptera, Lepidoptera, Orthoptera, and Phasmatodea, were analyzed. A neighbor joining distance phenogram identified several protein similarity classes that were characterized by highly conserved sequence motifs, including (A) N-terminal YTTKYDN(V/I)(N/D)(L/V)DEIL, (B) central DGKELKXX(I/L)PDAL, and (C) C-terminal KYDP. In contrast, three similarity classes were characterized by their diversion from these conserved motifs. The functional importance of conserved amino acid residues is discussed in relation to the crystal and NMR structures of MbraCSPA6.
Faculty of Agricultural Sciences, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
Kevin W
KW
Wanner
Les G
LG
Willis
David A
DA
Theilmann
Murray B
MB
Isman
Qili
Q
Feng
Erika
E
Plettner
D000595:Amino Acid Sequence; D000818:Animals; D000852:Anopheles / Q000235:genetics; D001483:Base Sequence; D002352:Carrier Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D017124:Conserved Sequence / Q000502:physiology*; D004330:Drosophila / Q000235:genetics; D029721:Drosophila Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D015723:Gene Library; D019476:Insect Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D018035:Receptors, Odorant / Q000032:analysis / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D018035:Receptors, Odorant; C109787:a10 protein, Drosophila; C045648:odorant-binding protein