TY - JOUR
T1 - Isolation and characterization of Schistosoma mansoni constitutive androstane receptor
AU - Hu, Rong
AU - Wu, Wenjie
AU - Niles, Edward G.
AU - LoVerde, Philip T.
N1 - Funding Information:
We thank Dr. Wade J. Sigurdson (Confocal Microscopy Facility, SUNY at Buffalo) for helping us obtain confocal images. This research was supported by a National Institute of Health Grant AI46762.
PY - 2006/7
Y1 - 2006/7
N2 - Full length cDNA clones encoding a Schistosoma mansoni homologue of vertebrate CAR/PXR/VDR group nuclear receptor, termed SmCAR were isolated from screening a S. mansoni adult worm cDNA library. SmCAR is a 702 amino acid protein which retains a typical domain organization of nuclear receptor superfamily members. A homology search demonstrated that SmCAR exhibits the highest homology with mouse constitutive androstane receptor (CAR). Like its orthologues from invertebrates, SmCAR contains a P box sequence of ESCKA in the DNA binding domain. The P box is important in determining the DNA binding specificity for nuclear receptors. SmCAR mRNA is expressed in every stage of S. mansoni life cycle with an elevated expression level in egg and cercaria stages. Two forms (78 and 81 kDa) of SmCAR protein were detected in schistosome worm extract by Western blot analysis. SmCAR protein was demonstrated to be widely distributed in adult worms by immunolocalization studies, being found in the subtegument in both male and female worms and in the ovaries, vitellaria and eggs in female worms. In vitro DNA binding assays demonstrated that SmCAR binds to the hsp27 ecdysone response element (EcRE) as well as schistosome p14 gene upstream region. The AGTGCA half site is essential for binding of SmCAR to the p14 gene upstream region. Therefore, AGTGCA probably serves as a high affinity binding half site for ESCKA containing nuclear receptors.
AB - Full length cDNA clones encoding a Schistosoma mansoni homologue of vertebrate CAR/PXR/VDR group nuclear receptor, termed SmCAR were isolated from screening a S. mansoni adult worm cDNA library. SmCAR is a 702 amino acid protein which retains a typical domain organization of nuclear receptor superfamily members. A homology search demonstrated that SmCAR exhibits the highest homology with mouse constitutive androstane receptor (CAR). Like its orthologues from invertebrates, SmCAR contains a P box sequence of ESCKA in the DNA binding domain. The P box is important in determining the DNA binding specificity for nuclear receptors. SmCAR mRNA is expressed in every stage of S. mansoni life cycle with an elevated expression level in egg and cercaria stages. Two forms (78 and 81 kDa) of SmCAR protein were detected in schistosome worm extract by Western blot analysis. SmCAR protein was demonstrated to be widely distributed in adult worms by immunolocalization studies, being found in the subtegument in both male and female worms and in the ovaries, vitellaria and eggs in female worms. In vitro DNA binding assays demonstrated that SmCAR binds to the hsp27 ecdysone response element (EcRE) as well as schistosome p14 gene upstream region. The AGTGCA half site is essential for binding of SmCAR to the p14 gene upstream region. Therefore, AGTGCA probably serves as a high affinity binding half site for ESCKA containing nuclear receptors.
KW - Constitutive androstane receptor (CAR)
KW - Ecdysone response element (EcRE)
KW - Nuclear receptor
KW - Schistosoma mansoni
KW - p14 female-specific gene
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U2 - 10.1016/j.molbiopara.2006.02.017
DO - 10.1016/j.molbiopara.2006.02.017
M3 - Article
C2 - 16603257
AN - SCOPUS:33646900513
VL - 148
SP - 31
EP - 43
JO - Molecular and Biochemical Parasitology
JF - Molecular and Biochemical Parasitology
SN - 0166-6851
IS - 1
ER -