• Reproductive and Developmental Biology
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• v.29 no.1
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• pp.19-24
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• 2005

The low density lipoprotein receptor-related protein 5 (LRP5) highly expressed in many tissues, including hepatocytes and pancreatic beta cells, can bind to apolipoprotein E. To evaluate in vivo roles of LRP5, we generated LRP5-deficient mice. LRP5 genomic DNA was isolated from TT2 embryonic stem (ES) cells. Targeting vector was constructed to disrupt an exon 18 of the mouse LRP5 gene and transfected into ES cells. Three homologous recombinants at LRP5 locus were identified from 178 G418-resistant clones. Chimeric males generated by morula aggregation technique were mated to C57BL/6 female mice. After achieving germ-line transmission, LRP5+/- females were crossed with LRP5+/- males to obtain LRP5-deficient mice. One line of mice lacking LRP5 gene was confirmed by Southern blotting. Such knock-out mice may serve as an effective animal model to study in vivo function of LRP5 gene.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.82-82
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• 2002

The Wnt signaling pathway plays pivotal roles in embryonic development and oncogenesis through various signaling molecules inculding Frizzled receptor, recently characterized LRP5/6 and Dickkopf protein. Although Wnt signaling has been characterized in both developmental and oncogenic processes, little is known about its function in the normal adult. The ability of LRP5 to bind apolipoprotein E(apoE) and the abundant expression of LRP5 transcripts in hepatocytes, raise the possibility that LRP5 plays a role in the hepatic clearance of ApoE-containing chylomicron remonants, a major plasma lipoprotein carrying diet-derived cholesterol. (omitted)

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.297-303
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• 2017

Leucine-responsive regulatory protein (LRP) is a regulatory protein of molecular weight 18.8 kDa and is widely known to regulate many metabolic and functional activities of operons in Escherichia coli. The gene for Lrp from Escherichia coli in pQE system of 6 ${\times}$ His-tagging was expressed and $^3H$-labeled protein, as well as the wild type Lrp, was purified. The crosslink experiments were performed to analyze the quaternary structure of Lrp at high of $5{\mu}M$ and at low concentrations below $0.3{\mu}M$ with cross linkers, such as glutaraldehyde, 1, 2, 3, 4-diepoxy-butane (DEB), and ethylene glycol bis (succinimidyl succinate) (EGS). In the experiments, we found that the Lrp protein can be formed higher conformation states of tetramer, hexamer, octamer, as well as dimeric state when incubated with the above cross linkers.

• BMB Reports
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• v.41 no.3
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• pp.230-235
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• 2008

LRP15 is a novel gene cloned from lymphocytic cells, and its function is still unknown. Bioinformatic data showed that LRP15 might be regulated by DNA methylation and had an important role in DNA repair. In this study, we investigate whether the expression of LRP15 is regulated by DNA methylation, and whether overexpression of LRP15 increases efficiency of DNA repair of UV-induced DNA damage in HeLa cells. The results showed (1) the promoter of LRP15 was hypermethylated in HeLa cells, resulting a silence of its expression. Gene expression was restored by a demethylating agent, 5-aza-2'-deoxycytidine, but not by a histone deacetylase inhibitor, trichostatin A; (2) overexpression of LRP15 inhibited HeLa cell proliferation, and the numbers of cells in the G2/M phase of the cell cycle in cells transfected with LRP15 increased about 10% compared with controls; (3) cyclin B1 level was much lower in cells overexpressing LRP15 than in control cells; and (4) after exposure to UV radiation, the LRP15-positive cells showed shorter comet tails compared with the LRP15-negative cells. From these results we conclude that the expression of LRP15 is controlled by methylation in its promoter in HeLa cells, and LRP15 confers resistance to UV damage and accelerates the DNA repair rate.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6663-6668
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• 2015

Background: Treatment failure in leukemia is due to either pharmacokinetic resistance or cell resistance to drugs. Materials and Methods: Gene expression of multiple drug resistance protein (MDR-1), multidrug resistance-related protein (MRP) and low resistance protein (LRP) was assessed in 45 pediatric ALL cases and 7 healthy controls by real time PCR. The expression was scored as negative, weak, moderate and strong. Results: The male female ratio of cases was 2.75:1 and the mean age was 5.2 years. Some 26/45 (58%) were in standard risk, 17/45(38%) intermediate and 2/45 (4%) in high risk categorie, 42/45 (93%) being B-ALL and recurrent translocations being noted in 5/45 (11.0%). Rapid early response (RER) at day 14 was seen in 37/45 (82.3%) and slow early response (SER) in 8/45 (17.7%) cases. Positive expression of MDR-1, LRP and MRP was noted in 14/45 (31%), 15/45 (33%) and 27/45 (60%) cases and strong expression in 3/14 (21%), 11/27 (40.7%) and 8/15 (53.3%) cases respectively. Dual or more gene positivity was noted in 17/45 (38%) cases. 46.5 % (7/15) of LRP positive cases at day 14 were in RER as compared to 100% (30/30) of LRP negative cases (p<0.05). All 8 (100%) LRP positive cases in SER had strong LRP expression (p=<0.05). Moreover, only 53.3% of LRP positive cases were in haematological remission at day 30 as compared to 100% of LRP negative cases (p=<0.05). Conclusions: Our study indicated that increased LRP expression at diagnosis in pediatric ALL predicts poor response to early treatment and hence can be used as a prognostic marker. However, larger prospective studies with longer follow up are needed, to understand the clinical relevance of drug resistance proteins.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.527-535
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• 2021

Sclerostin (SOST), a regulator of bone formation in osteocytes, inhibits the canonical Wnt signaling by interacting with low-density lipoprotein receptor-related protein 5/6 (LRP5/6) to prevent Wnt binding. Loss-of-function mutations of the SOST gene caused massive bone outgrowth and SOST-null mouse exhibited a high bone density phenotype. Therefore, SOST has been suggested as a promising therapeutic target for osteoporosis. A few previous studies with X-ray crystallography identified the binding interfaces between LRP6 and SOST, but there are limitations in these studies as they used truncated SOST protein or SOST peptide. Here, we analyzed the conformational dynamics of SOST-LRP6 E1E2 complex using hydrogen/deuterium exchange mass spectrometry (HDX-MS). We examined the effect of the C-terminal tail of SOST on LRP6 conformation upon complex formation. HDX-MS analysis suggested a new potential binding interface for the C-terminal region of SOST that was missing from the previous crystal structure of the SOST-LRP6 E1E2 complex.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6311-6314
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• 2013

Background: While 5-port laparoendoscopic radical prostatectomy is standard practice, efforts have been focused in developing a single port surgery for cosmetic reasons. However, this is still in the pioneering stage considering the challenging nature of the surgical procedures. We have therefore focused on reduced port surgery, using only 2-ports. In this study, we compared 2-port laparoendoscopic radical prostatectomy (2-port RP) and conventional 5-port laparoscopic radical prostatectomy (LRP) for clinically localized prostate carcinoma and evaluated the potential advantages of each. Materials and Methods: From January 2010 to December 2010, all 23 patients with clinically localized prostate cancer underwent LRP. Starting November, 2010, when we introduced the reduced port approach, we performed this procedure for 22 consecutive patients diagnosed with early-stage prostate cancer (cT1c, cT2N0). The patients were matched 1:1 to 2-port RP or LRP for age, preoperative serum PSA level, clinical stage, biopsy and pathological Gleason grade, surgical margin status, pad-free rates and post-operative pain. Results: There was a significant difference in operative time between the 2-port RP and LRP groups ($286.5{\pm}63.3$ and $351.8{\pm}72.4$ min: p=0.0019, without any variation in blood loss (including urine) ($945.1{\pm}479.6$ vs $1271.1{\pm}871.8ml$: p=0.13). The Foley catheter indwelling period was shorter in the 2 port RP group, but without significance ($5.6{\pm}1.8$ vs $8.0{\pm}5.6$ days: p=0.057) and the total perioperative complication rates for 2 port RP and LRP were comparable at 4.5% and 8.7% (p=0.58). There was an improvement in pad-free rates up to 6 months follow-up (p=0.090), and significantly improvement at 1 year (p=0.040). PSA recurrence was 1 (4.5%) in 2-port RP and 2 (8.7%) in LRP. Continuous epidural anesthesia was used in most of LRP patients (95.7%) and in early 2-port RP patients (40.9%). In these patients, average total amount of Diclofenac sodium was 27.8mg/patient in 2-port RP and 50.0mg/patient in LRP. Conclusions: Thus the reduced port approach is as efficacious as LRP in terms of many outcome measures, with significant cosmetic advantages and reduction in post surgical pain. This method can be readily performed safely and therefore can be recommended as a standard laparoscopic surgery for prostate cancer in the future.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.77-82
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• 2021

As malaria remains a major health problem worldwide, various diagnostic tests have been developed, including microscopy-based and rapid diagnostic tests. LabChip real-time PCR (LRP) is a small and portable device used to diagnose malaria using lab-on-a-chip technology. This study aimed to evaluate the diagnostic performance of LRP for detecting malaria parasites. Two hundred thirteen patients and 150 healthy individuals were enrolled from May 2009 to October 2015. A diagnostic detectability of LRP for malaria parasites was compared to that of conventional RT-PCR. Sensitivity of LRP for Plasmodium vivax, P. falciparum, P. malariae, and P. ovale was 95.5%, 96.0%, 100%, and 100%, respectively. Specificity of LRP for P. vivax, P. falciparum, P. malariae, and P. ovale was 100%, 99.3%, 100%, and 100%, respectively. Cohen's Kappa coefficients between LRP and CFX96 for detecting P. vivax, P. falciparum, P. malariae, and P. ovale were 0.96, 0.98, 1.00, and 1.00, respectively. Significant difference was not observed between the results of LRP and conventional RT-PCR and microscopic examination. A time required to amplify DNAs using LRP and conventional RT-PCR was 27 min and 86 min, respectively. LRP amplified DNAs 2 times more fast than conventional RT-PCR due to the faster heat transfer. Therefore, LRP could be employed as a useful tool for detecting malaria parasites in clinical laboratories.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.941-942
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• 2009

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.33-40
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• 2012

This study was carried out to investigate the effect of the addition of lotus (Nelumbo nucifera) root and leaf powder on the quality characteristics of pork patties. The pork patties were of four types: nothing added (CTL), 0.5% lotus root powder added (LRP), 0.25% lotus root and 0.25% lotus leaf powder added (LRLP), and 0.5% lotus leaf powder added (LLP). There was no significant difference in $L^*$ value (whiteness), cohesiveness, gumminess, chewiness, water holding capacity, VBN content, and total bacterial amount. The moisture was highest in CTL, protein was highest in LRLP, fat was highest in LRLP and LLP, and ash was highest in LRLP (p<0.05). The total polyphenol content of the CTL, LRP, LRLP, and LLP were 3.34, 3.64, 3.90 and 3.90 mg/100 g, respectively. The $a^*$ value was highest in CTL, and the $b^*$ value of LRLP and LLP were higher than those of CTL and LRP (p<0.05). The hardness of CTL and LRP were higher than those of LRLP and LLP, and springiness was lowest in LLP (p<0.05). The cooking loss, thickness change, diameter changes, and pH were highest in CTL (p<0.05). The TBARS was highest in CTL, and was lowest in LLP (p<0.05).