Concentration: | 1 mg / ml, determined by the Lowry method |
Source: | From fresh human plasma that has tested negative for Hepatitis C, HIV-I and HIV-II antibodies as well as Hepatitis surface antigens. |
Purification: | After series ultracentrifugation, Low Density Lipoprotein (LDL) is isolated from human plasma. Water-soluble Apo B-100 is prepared from delipidated LDL. |
Purity: | ≥ 98% by SDS-PAGE |
Buffer: | 20 mM Tris-HCl, 140 mM NaCl, 0.5 mM EDTA, 0.02 % NaN3, pH 7.4; Preserved with 50% glycerol. |
Storage: | -20°C for long-term storage, 4°C for short- term storage. Aliquot to avoid repeated freezing and thawing. |
Importance
ApoB exists in human plasma in two isoforms, ApoB-48 (Chen et al., 1987) and Apo B-100 (Wei et al., 1985, Yang et al., 1986a; 1989a,b; 1990; Chen et al., 1986; Yang et al., 1990, Yang and Pownall, 1992). Apo B-100 is the major physiological ligand for the LDL receptor. Apo B-100 is a large monomeric protein, containing 4536 amino acids (m.w. 515 kDa, Yang et al., 1986b).
Apo B-100 is synthesized in the liver and is required for the assembly of VLDL. It is found in LDL and VLDL after the removal of the Apo A, E and C. Apo B-48 is present in chylomicrons and their remnants. It is essential for the intestinal absorption of dietary lipids. Apo B levels correlate with the risk of coronary disease.
The Apo B protein is directly involved in the retention of LDL with the arterial wall (Olofsson and Boren, 2012). Apo B-48 is synthesized in the small intestine. It comprises approximately half of the N-terminal region of ApoB-100 and is the result of posttranscriptional mRNA editing by a stop codon in the intestine not found in the liver.
Chen, S., G. Habib, C. Yang, Z. Gu, B. Lee, S. Weng, S. Cai, J. Deslypere, M. Rosseneu, and Al. Et. "Apolipoprotein B-48 Is the Product of a Messenger RNA with an Organ-specific In-frame Stop Codon." Science 238 (1987): 363- 66.
Olofsson, S.-O., and J. Boren. "Apolipoprotein B Secretory Regulation by Degradation." Arteriosclerosis, Thrombosis, and Vascular Biology 32 (2012): 1334-338.
Wei, C. F., S. H. Chen, C. Y. Yang, Y. L. Marcel, R. W. Milne, W. H. Li, J. T. Sparrow, A. M. Gotto, and L. Chan. "Molecular Cloning and Expression of Partial cDNAs and Deduced Amino Acid Sequence of a Carboxyl-terminal Fragment of Human Apolipoprotein B-100." Proceedings of the National Academy of Sciences 82 (1985): 7265- 269.
Yang, Chao-Yuh, and Pownall, H.J. "In Structure and Function of Plasma Apolipoproteins." Structure and Function of Apolipoproteins. Boca Raton, Fla.: CRC, 1992.
Yang, Chao-Yuh, T. W. Kim, S. A. Weng, B. R. Lee, M. L. Yang, and A. M. Gotto. "Isolation and Characterization of Sulfhydryl and Disulfide Peptides of Human Apolipoprotein B-100." Proceedings of the National Academy of Sciences 87 (1990): 5523-527.
Yang, Chao-Yuh, Z. W. Gu, S. A. Weng, T. W. Kim, S. H. Chen, H. J. Pownall, P. M. Sharp, S. W. Liu, W. H. Li, and A. M. Gotto. "Structure of Apolipoprotein B-100 of Human Low Density Lipoproteins." Arteriosclerosis, Thrombosis, and Vascular Biology 9 (1989a): 96-108.
Yang, Chao-Yuh, Zi-Wei Gu, Lawrence Chan, Henry J. Pownall, and Antonio M. Gotto. "Structure and Functional Domains of Human Apolipoprotein B-100: A Strategy to Elucidate the Structure Information of a Large Protein." Methods in Protein Sequence Analysis (1989b): 466-74.
Yang, Chao-Yuh, San-Hwan Chen, Sandra H. Gianturco, William A. Bradley, James T. Sparrow, Masako Tanimura, Wen-Hsiung Li, Doris A. Sparrow, Hans Deloof, Maryvonne Rosseneu, Fu-Shin Lee, Zi-Wei Gu, Antonio M. Gotto, and Lawrence Chan. "Sequence, Structure, Receptor-binding Domains and Internal Repeats of Human Apolipoprotein B-100." Nature 323 (1986a): 738-42.
Citations
[P07] | 2006 | Yokoyama, Yuichiro; Kuramitsu, Yasuhiro; Takashima, Motonari; Iizuka, Norio; Terai, Shuji; Oka, Masaaki et al. (2006): Protein level of apolipoprotein E increased in human hepatocellular carcinoma. In International journal of oncology 28 (3), pp. 625–631. |
[P07] | 2005 | Kinoshita, Makoto; Kojima, Masaaki; Matsushima, Teruhiko; Teramoto, Tamio (2005): Determination of apolipoprotein B-48 in serum by a sandwich ELISA. In Clinica Chimica Acta 351 (1-2), pp. 115–120. DOI: 10.1016/j.cccn.2004.08.008. |