• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4016-4020
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• 2011

A number of mimetic peptides of apolipoprotein A-I, a major component for high density lipoproteins (HDL), were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). A mimetic peptide for A12 epitope against apolipoprotein A-I was selected as FVLVRDTFPSSVCCP(pA2) exhibiting 45% homology with Apo A-I in the BLAST search. Solution structure determination of this mimotope was made by using 2D-NMR data and NMR-based distance geometry (DG)/molecular dynamic calculations. The resulting DG structures had low penalty value of 0.4-0.6 ${\AA}^2$ and the total RMSD of 0.7-1.7 ${\AA}$. The mimotope pA2 exhibited a characteristic ${\beta}$-turn conformation from Val[2] to Phe[8] near Pro[9] residue.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3425-3428
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• 2011

Apolipoprotein A-I (Apo A-I) is a major component for high density lipoproteins (HDL). A number of mimetic peptides of Apo A-I were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). Mimetic peptide for A12 epitope against Apo A-I was selected as CPFARLPVEHHDVVGL (pA1). From the BLAST search, the mimetic peptide pA1 had 40% homology with Apo A-I. As a result of the structural determination of this mimotope using homo/hetero nuclear 2D-NMR techniques and NMR-based distance geometry (DG)/molecular dynamic (MD) computations, DG structure had low penalty value of 0.3-0.7 ${\AA}^2$ and the total RMSD was 0.6-1.6 ${\AA}$. The mimotope pA1 exhibited characteristic conformation including a ${\beta}$-turn from Pro[7] to His[11].

• Journal of Aquaculture
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• v.20 no.1
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• pp.65-72
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• 2007

Full length complementary DNA encoding apolipoprotein A-I (apoA-I) was isolated and characterized in mud loach (Misgurnus mizolepis). Mud loach apoA-I cDNA encoding 24 bp of 5'-untranslated region (UTR), 762 bp of single open reading frame (ORF) consists of 254 amino acids and 293 bp of 3'-UTR excluding stop codon and poly (A+) tail. Two overlapping polyadenylation signals (AATAAAATAAA) was found 9 bp prior to the poly (A+) tail. Mud loach apoA-I represented considerable homology to those from other teleost species at amino acid level with conserving common features of vertebrate apoA-I. Molecular phylogenetic analysis inferred the phylogenetic hypothesis that was generally in accordance with the previous taxonomic relationship. Apolipoprotein A-I mRNA was detected in various tissues, but the mRNA levels were quite varied depending on tissues based on semi-quantitative RT-PCR. Liver and brain showed the significantly higher levels of apoA-I transcripts than other tissues. mRNA expression of apoA-I was quite low in very early stage of embryonic development, however dramatically enhanced from 8 hours post fertilization. This increased mRNA level was retained consistently up to 14 days post hatching.

• Molecules and Cells
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• v.26 no.3
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• pp.291-298
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• 2008

Human karyopherin ${\beta}3$, highly homologous to a yeast protein secretion enhancer (PSE1), has often been reported to be associated with a mediator of a nucleocytoplasmic transport pathway. Previously, we showed that karyopherin ${\beta}3$ complemented the PSE1 and KAP123 double mutant. Our research suggested that karyopherin beta has an evolutionary function similar to that of yeast PSE1 and/or KAP 123. In this study, we performed yeast two-hybrid screening to find a protein which would interact with karyopherin ${\beta}3$ and identified apolipoprotein A-I (apo A-I), a secretion protein with a primary function in cholesterol transport. By using in vitro binding assay, co-immunoprecipitation, and colocalization studies, we defined an interaction between karyopherin ${\beta}3$ and apo A-I. In addition, overexpression of karyopherin ${\beta}3$ significantly increased apo A-I secretion. These results suggest that karyopherin ${\beta}3$ plays a crucial role in apo A-I secretion. These findings may be relevant to the study of a novel function of karyopherin ${\beta}3$ and coronary artery diseases associated with apo A-I.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.88-97
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• 2008

Lipoproteins are complexes of lipids and specific apolipoproteins that are involved in lipid transport and redistribution among various tissues. In this study, we isolated full-length apolipoprotein cDNA sequences encoding apolipoprotein A-I (apoA-I), apoE, apoC-II, and apo-14 kDa in barred knifejaw, Oplegnathus fasciatus. In addition, we reconstructed phylogenetic trees and investigated mRNA tissue distributions. Alignment analyses of amino acid sequences revealed that secondary structures of the polypeptides apoA-I, apoE, and apoC-II in barred knifejaw are well conserved with their teleostean and mammalian counterparts in terms of characteristic tandem repetitive units forming amphipathic ${\alpha}$-helices. Both the sequence alignment data and cleavage sites of apo-14 kDa indicated a clear differentiation between Percomorpha and Cypriniformes. Meanwhile, the phylogenetic trees of apolipoprotein sub-families suggested that the common ancestor prior to the split of the Actinopterygii (ray-finned fishes) and Sarcopterygii (tetrapods) would have possessed the primordial protein-encoding genes. Tissue distribution of each apolipoprotein transcript determined by semi-quantitative RTPCR showed that barred knifejaw apoA-I transcripts were more or less ubiquitously expressed in the liver, intestines, brain, muscle, spleen, and kidney. The most striking difference from previous observations on barred knifejaw was the ubiquitous expression of apoE across all somatic tissues. Barred knifejaw apoC-II showed tissue-specific expression in the liver and intestines, while the liver and brain were the major sites of apo-14kDa mRNA synthesis.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.949-958
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• 2008

This study was carried out to examine the association of age, nutrient intake, alcohol drinking and smoking on serum lipid and apolipoprotein levels in 100 healthy adults (54 males and 46 females). The serum total cholesterol, low density lipoprotein cholesterol (LDL-C) (p<0.05), apolipoprotein B (Apo B) levels, LDL-C:high density lipoprotein cholesterol (HDL-C) ratio, Apo B:apolipoprotein(Apo A-I) ratio and atherogenic index (AI) (p<0.001) were significantly higher in males than females, but HDL-cholesterol level was significantly lower (p<0.01) in males than females. The plasma ascorbic acid concentration had no difference in both genders. Most of nutrient intakes except Ca, vitamin A and vitamin $B_2$ were higher than RI (Recommended intake) in both males and females. The meal frequency per day was significantly higher (p<0.01) in males than females, while meal speed, the heaviest meal, meal quantity and meal regularity had no significant differences. The rates of drinking and smoking were significantly higher (p<0.01) in males (59.3%, 37.2%) than females (17.3%, 6.9%). The age was positively correlated with triglyceride level in males (p<0.05), and with total cholesterol (p<0.001), LDL-cholesterol (p<0.001), Apo B (p<0.01), LDL-C:HDL-C ratio (p<0.01), Apo B:Apo A-I ratio (p<0.05) and AI (p<0.01) in females. The levels of serum lipid and apolipoprotein were more correlated with protein intake than other macronutrient intakes in males, while those in females were more correlated energy, carbohydrate and lipid intakes than protein intake. The effect of drinking on serum lipid and apolipoprotein levels was bigger in males than females, while the effect of smoking on those was bigger in females than males. The plasma ascorbic acid concentration was positively correlated with HDL-cholesterol (p<0.05), Apo A-I levels (p<0.001), whereas negatively correlated with Apo B:Apo A-I ratio (p<0.05) in males. And that was positively correlated with HDL-cholesterol (p<0.05) in females. These results suggest that moderate macronutrient intake, less alcohol consumption and non-smoking were necessary to maintain healthy lipid profile with aging in adults.

• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.196-196
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• 2005

• Molecules and Cells
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• v.38 no.6
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• pp.573-579
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• 2015

Apolipoprotein A-I and A-IV are protein constituents of high-density lipoproteins although their functional difference in lipoprotein metabolism is still unclear. To compare anti-atherogenic properties between apoA-I and apoA-4, we characterized both proteins in lipid-free and lipidbound state. In lipid-free state, apoA4 showed two distinct bands, around 78 and $67{\AA}$ on native gel electrophoresis, while apoA-I showed scattered band pattern less than $71{\AA}$. In reconstituted HDL (rHDL) state, apoA-4 showed three major bands around $101{\AA}$ and $113{\AA}$, while apoA-I-rHDL showed almost single band around $98{\AA}$ size. Lipid-free apoA-I showed 2.9-fold higher phospholipid binding ability than apoA-4. In lipid-free state, $BS_3$-crosslinking revealed that apoA-4 showed less multimerization tendency upto dimer, while apoA-I showed pentamerization. In rHDL state (95:1), apoA-4 was existed as dimer as like as apoA-I. With higher phospholipid content (255:1), five apoA-I and three apoA-4 were required to the bigger rHDL formation. Regardless of particle size, apoA-I-rHDL showed superior LCAT activation ability than apoA-4-rHDL. Uptake of acetylated LDL was inhibited by apoA-I in both lipid-free and lipid-bound state, while apoA-4 inhibited it only lipid-free state. ApoA-4 showed less anti-atherogenic activity with more sensitivity to glycation. In conclusion, apoA-4 showed inferior physiological functions in lipid-bound state, compared with those of apoA-I, to induce more pro-atherosclerotic properties.

• Biomedical Science Letters
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• v.17 no.4
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• pp.347-353
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• 2011

The definite mechanism in the control of triglyceride metabolism is not well understood. Nowadays, it has been known that the polymorphism of apolipoprotein C-III $Sst$ I was an important candidate for contributing to the control of triglyceride metabolism. In 298 Korean women aged 30 years or more, the genotypes of apolipoprotein C-III $Sst$ I were statistically compared with total blood cholesterol, triglyceride, high density lipoprotein, fasting blood sugar and hemoglobin A1c. Multiple logistic regression analysis was carried out to compare the odd-ratios of hypertriglyceridemia, hypercholesterolemia and diabetes mellitus with them. The differences among the polymorphic types ($S_1S_1$, $S_1S_2$, and $S_2S_2$) were not statistically significant in the distribution of triglyceride, total cholesterol, high density lipoprotein, fasting blood sugar, and hemoglobin A1c. There were not statistically significant in the odds ratios of the hypertriglyceridemia, hypercholesterolemia, and diabetes mellitus, neither. Those were not statistically significant. This study did not show that there was any association between the polymorphism of apolipoprotein C-III $Sst$ I and various laboratory values-total blood cholesterol, triglyceride, high density lipoprotein, fasting blood sugar and hemoglobin A1c.

• BMB Reports
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• v.30 no.6
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• pp.390-396
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• 1997

A sandwich-type enzyme-linked immunosorbent assay (ELISA) for the quantification of human apolipoprotein A-I (apoA-I) was developed using monoclonal antibodies. For this assay, we used three monoclonal antibodies to trap and detect apo A-I. HDAI16 and HDA15 monoclonal antibodies were used for trapping apoA-I and HDAI8 monoclonal antibody was for detecting apoA-I. These three monoclonal antibodies were produced by immunizing mice with high density lipoprotein (HDL) isolated from human plasma. By immunoblot analysis, these three monoclonal antibodies were specific to apoA-I and showed no cross-reactivities with other plasma proteins. The results of competition assays for epitope cross-reactivity test also verified that these monoclonal antibodies identified separate and distinct epitopes on HDL and apoA-I. Affinity constants of monoclonal antibodies were measured by ELISA. Their association constants ranged from $10^7$ to $10^8$ $M^{-1}$. For this assay, pure apoA-I was isolated by affinity chromatography using monoclonal antibodies. In this sandwich assay, the amount of HRP-labeled HDAI8 bound to apoA-I trapped by HDAI16 and HDAI5 was proportional to apoA-I concentration in the range of 0 to 500ng/ml. ApoA-I concentration in plasma was calculated from the linear regression equation of standard curve. The precision and reliability of the assays are reflected in the low intra-and interassay coefficients of variation that averaged 3.25% and 4.30%, respectively. This assay is sensitive, simple, reproducible, convenient in incubation interval, and does not use radioisotope: thus it can be widely applied in clinical laboratories.