Biomedical subjects

Bong Hee Lee

Publications and source records attributed to Bong Hee Lee.

5 recordsLinked to original sources

PubMed2003

Vasoactive intestinal peptide (VIP) and VIP mRNA decrease in the cerebral cortex of nNOS knock-out(-/-) mice.

Although there is much evidence showing that NO regulates the release of VIP in several areas, there is no report about the influence of NO on VIP in the cerebral cortex. We therefore examined changes in VIP expression in the cerebral cortex of nNOS knock-out(-/-) mice using immunohistochemistry and in situ hybridization. The nNOS((-/-)) mice had significantly fewer VIP-immunoreactive neurons than the control mice and the VIP mRNA as well as the VIP-immunoreactivity of the individual neuron was decreased in the nNOS((-/-)) mice. The first demonstration of decrease in VIP expression in the cerebral cortex of nNOS((-/-)) mice may provide useful data for investigating the relation between NO and VIP in the cerebral cortex and the mechanisms of many functions of these two neurotransmitters.

Animals↗

PubMed2003

Wax moth, Galleria mellonella fat body receptor for high-density lipophorin (HDLp).

To identify and characterize the HDLp (high-density lipophorin) receptor from Galleria mellonella (LpRGm), we used techniques of ligand blotting. This method was, to our knowledge, first used to characterize the lipophorin receptor (LpR) in insects. LpRGm had an approximate molecular weight of 97 kDa under non-reducing conditions and bound the HDLp specifically. The time-course of lipophorin binding to their receptor protein was rapid. The binding of lipophorins to their receptors was saturable with a Kd of 34.33+/-4.67 microg/ml. Although Ca2+ was essentially required in the binding of HDLp to their receptors, interestingly increasing concentration of Ca2+ has shown to have a slight inhibitory effect. EDTA was used here as Ca2+ chelating reagent, because Mg2+ in the binding buffer did not affect the binding of HDLp to their receptors, and inhibited the binding of HDLp and LpRGm absolutely. Suramin (polysulfated polycyclic hydrocarbon), known to inhibit the binding of lipoproteins to their receptors, effectively abolished the binding of HDLp to their receptors. LpRGm showed the stage specific binding activity especially in day 1-3 last instar larval, prepupal, and day 1-3 adult stages.

Animals↗

PubMed2003

Cloning and expression of male-specific protein (MSP) from the hemolymph of greater wax moth, Galleria mellonella L.

Male-specific protein (MSP) is a soluble protein that accumulates in high amounts in the hemolymph and other organs of adult male wax moth. The MSP was purified from adult male wax moth by gel filtration and reversed phase column chromatography, and its amino acid sequence was determined. Because of blocked N-terminus, several internal amino acid sequences of MSP were obtained by the in-gel digestion method using trypsin. RT-PCR was conducted using degenerate primers designed from the internal amino acid sequences. 5'-RACE PCR was used to obtain the complete coding region and 5'-UTR sequence. The full length MSP cDNA sequence encodes a 239 amino acid polypeptide with an 18 amino acid signal peptide. The putative mature MSP has a molecular mass of 24,317 Da and an isoelectric point (pI) of 6.00, but shows a molecular mass of 27 kDa on SDS-PAGE. Sequence alignment showed a significant similarity between MSP and juvenile hormone binding proteins (JHBPs) of several lepidopteran species, including G. mellonella.

Amino Acid Sequence↗

PubMed2003

Effects of 20-hydroxyecdysone and serotonin on neurite growth and survival rate of antennal lobe neurons in pupal stage of the silk moth Bombyx mori in vitro.

Effects of 20-hydroxyecdysone and serotonin on the morphological development and the survival of antennal lobe neurons from day-2 pupal brains of the silk moth Bombyx mori were investigated in vitro. Four morphologically distinct neuronal types could be identified in the cultured antennal lobe neurons: unipolar, bipolar, multi-polar and projection neurons. Antennal lobe neurons in culture with 20-hydroxyecdysone and serotonin showed different patterns of the morphological development from those described in Manduca sexta. Projection neurons extend their neurites remarkably by 20-hydroxyecdysone in B. mori, but there is no extension from antennal lobe neurons in M. sexta. Multi-polar neurons conspicuously increase only formation of new branches from their primary neurites by serotonin in B. mori, but there are both extension and branching of the neurites in M. sexta. On day-5, antennal lobe neurons in lower titers of 20-hydroxyecdysone had significantly higher survival rates than those in higher titers. Neurons cultured for 7 days at different levels of 20-hydroxyecdysone generally showed significantly lower survival rates than neurons cultured for 5 days under the same conditions.

Animals↗

PubMed2002

Molecular characterization of a cDNA from the silk moth Bombyx mori encoding Manduca sexta allatotropin peptide.

Allatotropin is a 13-residue amidated neuropeptide isolated from pharate adult heads of the tobacco hornworm, Manduca sexta and strongly stimulates biosynthesis of juvenile hormones in adults, but not larval, lepidopteran corpora allata. From a Bombyx mori midgut cDNA library, a cDNA that encodes a 130-amino-acid polypeptide containing M. sexta allatotropin sequence was isolated. The B. mori allatotropin cDNA consists of 1196 nucleotides. The encoded allatotropin peptide is identical to that isolated from M. sexta and that predicted from Pseudaletia unipuncta, with 84% and 81% identity in the amino acid sequence of the allatotropin peptide precursor, respectively. M. sexta allatotropin is flanked by two different endoproteolytic cleavage sites within the precursor of the B. mori allatotropin peptide. Evidence from northern blotting of B. mori tissues showed that the allatotropin gene is expressed in the cells of midgut, head and integument with different transcription amount, but not in the fat body and silk gland. Midgut has also a number of allatotropin-immunoreactive cells and nerve fibers. These results will provide valuable information in understanding the AT gene of insects.

Amino Acid Sequence↗