Human LBP-32/MGR is a repressor of the P450scc in human choriocarcinoma cell line JEG-3.

Steroid hormones regulate a wide range of physiologic functions in humans. The cholesterol side-chain cleavage enzyme P450scc regulates the initial step of biosynthesis of all steroid hormones. We investigated the expression of P450scc by studying a potential regulator of P450scc, LBP-32/MGR. Using a Northern blot, we found that LBP-32/MGR mRNA was expressed mainly in the human placenta. Using radiation hybrid mapping, we identified LBP-32/MGR on human chromosome 2p25. Recombinant LBP-32/MGR protein bound preferentially to a DNA fragment from the promoter of P450scc in vitro and exhibited clear nuclear localization in transfected cells. Luciferase reporter gene assays showed that LBP-32/MGR specifically repressed transcriptional activation of the human P450scc promoter. Because placental P450scc expression is essential for pregnancy and steroid biosynthesis, the placental expression and transcriptional repressor activity of LBP-32/MGR in JEG-3 cells suggest it has a role as a transcriptional modulator of steroid biosynthesis.

Placenta2007 Feb-Mar,28(2-3).

Protein Name:LBP
Gene Name:LBP


Recombinant Human LBP
(CatNo. C370)

Recombinant Human Lipopolysaccharide-Binding Protein/LBP produced by transfected human cells is a secreted protein with sequence (Ala26-Val481) of human LBP fused with a polyhistidine tag at the C-terminus.

Lipopolysaccharide binding protein (LBP) is a plasma protein, belongs to a member of structurally and functionally related proteins which includes bactericidal permeability-increasing protein (BPI), plasma cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP). It is involved in the acute-phase immunologic response to gram-negative bacterial infections. In cooperation with BPI. LBP binds LPS and interacts with the CD14 receptor, most likely playing a role in regulating LPS-dependent monocyte responses. Studies suggest that LBP is necessary for the rapid acute-phase response to LPS but not for the clearance of LPS from circulation. Finally, t The LBP gene is found on chromosome 20, directly downstream of the BPI gene.