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S C Rall

Publications and source records attributed to S C Rall.

78 records · Page 5Linked to original sources
PubMed1969

Histone structure: asymmetric distribution of lysine residues in lysine-rich histone.

Structural studies on a very lysine-rich histone show that the carboxyl-terminal half of the molecule is enriched in lysine (and proline). which suggests that it is a site for binding to DNA. The amino-terminal half. containing most of the acidic residues. resembles small, nonhistone proteins and so might have specificity for factors other than DNA.

Amino Acid Sequence↗
PubMedDate not supplied

Complete protein sequence and identification of structural domains of human apolipoprotein B.

Epidemiological, pathological and genetic studies show a strong positive correlation between elevated plasma concentrations of low-density lipoprotein (LDL) cholesterol and the risk of premature coronary heart disease. Apolipoprotein (apo) B-100 is the sole protein component of LDL and is the ligand responsible for the receptor-mediated uptake and clearance of LDL from the circulation. Apo B-100 is made by the liver and is essential for the assembly of triglyceride-rich very low-density lipoproteins (VLDL) in the cisternae of the endoplasmic reticulum and for their secretion into the plasma. VLDL transports triglyceride to peripheral muscle and adipose tissue, where the triglyceride is hydrolysed by lipoprotein lipase. The resultant particle, relatively enriched in cholesteryl ester, constitutes LDL. LDL delivers cholesterol to peripheral tissues where it is used for membrane and steroid hormone biosynthesis and to the liver, the only organ which can catabolize and excrete cholesterol. Plasma LDL levels are therefore determined by the balance between their rate of production from VLDL and clearance by the hepatic LDL (apo B/E) receptor pathway. Here we report the complete 4,563-amino-acid sequence of apo B-100 precursor (relative molecular mass (Mr) 514,000 (514K] determined from complementary DNA clones. Numerous lipid-binding structures are distributed throughout the extraordinary length of apo B-100 and must underlie its special functions as a nucleus for lipoprotein assembly and maintenance of plasma lipoprotein integrity. A domain enriched in basic amino-acid residues has been identified as important for the cellular uptake of cholesterol by the LDL receptor pathway.

Amino Acid Sequence↗
PubMedDate not supplied

Isolation and characterization of several plasma apolipoproteins of common marmoset monkey.

To explore the potential of the common marmoset monkey (Callithrix jacchus) as a model for human plasma lipoprotein metabolism, several marmoset apolipoproteins were isolated and characterized in this study. Based on several properties, including molecular weight, amino acid composition, and sequence, the marmoset apolipoproteins are strikingly similar to human apolipoprotein (apo) A-I, A-II, C-III, and A-IV. The first 54 residues of marmoset apo A-I showed 87% sequence identity with the corresponding region of human apo A-I. Amino-terminal sequence analysis of a minor basic apo A-I isoform revealed that it contained an amino-terminal hexapeptide extension (Arg-His-Phe-Gln-Gln-) identical to that found in human proapo A-I. Like apo A-II in most nonhuman primates, marmoset apo-A-II differed from human apo A-II in that it did not contain cysteine and therefore existed as a monomer. The complete amino acid sequence of marmoset apo A-II was deduced. The protein contains 77 amino acids, as does human apo A-II, and showed an 82% identity with its human equivalent. In both species, apo C-III and E had similar amino-terminal sequences and amino acid compositions. Like human apo E, marmoset apo E contained minor sialylated isoforms. However, unlike human apo C-III, no sialyated isoforms of marmoset apo C-III were observed. In addition, the marmoset possessed an apolipoprotein whose molecular weight and amino acid composition were similar to those of human apo A-IV. The close structural similarities between corresponding marmoset and human apolipoproteins indicate that the marmoset monkey will be useful as a model for human lipoprotein metabolism.

Amino Acid Sequence↗