THE NATURE OF TWO COMPONENTS OF PIG MUCOSAL HEPARIN, SEPARATED BY ELECTROPHORESIS IN AGAROSE GEL

Kinetoplast DNA, the mitochondrial DNA in trypanosomes, is a giant network containing topologically interlocked minicircles. Replication occurs on free minicircles that have been detached from the network. In this paper, we report studies on the synthesis and processing of the minicircle L and H strands. Analysis of free minicircles from Trypanosoma equiperdum by two-dimensional agarose gel electrophoresis indicated that elongating L strands are present on theta structures. Hybridization studies indicated that L-strand elongation is continuous and unidirectional, starting near nucleotide 805 and proceeding around the entire minicircle. The theta structures segregate into monomeric progeny minicircles, and those with a newly synthesized L strand have a 8-nucleotide gap between nucleotides 805 and 814 (J. M. Ntambi, T. A. Shapiro, K. A. Ryan, and P. T. Englund, J. Biol. Chem. 261:11890-11895, 1986). These molecules are reattached to the network, where repair of the gap takes place. Of the molecules labeled during a 10-min pulse with [3H]thymidine, gap filling occurred on half within about 15 min and on virtually all by 60 min; however, there was no detectable covalent closure of the newly synthesized L strand by 60 min.

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Evaluation of lipoproteins and apolipoproteins in serum of a Tangier patient by micro-scale two-dimensional electrophoresis.

Clinical Chemistry ◽

10.1093/clinchem/33.4.468 ◽

1987 ◽

Vol 33 (4) ◽

pp. 468-472 ◽

Cited By ~ 8

Author(s):

T Manabe ◽

S Visvikis ◽

M F Dumon ◽

M Clerc ◽

G Siest

Keyword(s):

Molecular Mass ◽

Gel Electrophoresis ◽

Sodium Dodecyl ◽

Disease Patient ◽

High Density Lipoproteins ◽

Two Dimensional ◽

High Concentration ◽

Two Dimensional Electrophoresis ◽

Micro Scale ◽

Dimensional Electrophoresis

Abstract We examined lipoproteins and apolipoproteins in serum of a Tangier-disease patient. We used three different techniques of micro-scale two-dimensional electrophoresis: (a) no denaturants; (b) with sodium dodecyl sulfate (SDS) used only in the slab gel electrophoresis; (c) and with urea and a detergent used in isoelectric focusing and with SDS in slab gel electrophoresis. By technique a, an extremely low concentration of high-density lipoproteins (HDL) in the Tangier serum was seen, and lipoproteins that cannot form HDL complexes were detected as multiple spots in the acidic (pl 4 approximately 5) and relatively low apparent molecular mass (20,000 approximately 80,000) region. By technique b, Tangier low-molecular-mass lipoproteins were dissociated into their constituent apolipoproteins, and we observed a higher proportion of apoC-III, together with lower proportions of apoA-I and apoA-II, than in the normal HDL fraction. Technique c showed the total content of apolipoproteins in the whole Tangier serum, as several workers have reported. The presence of low-molecular-mass lipoproteins and a high concentration of apoC-III in this lipoprotein fraction characterized the Tangier serum.

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Synthesis and processing of kinetoplast DNA minicircles in Trypanosoma equiperdum.

Molecular and Cellular Biology ◽

10.1128/mcb.9.8.3212 ◽

1989 ◽

Vol 9 (8) ◽

pp. 3212-3217 ◽

Cited By ~ 25

Author(s):

K A Ryan ◽

P T Englund

Keyword(s):

Mitochondrial Dna ◽

Gel Electrophoresis ◽

Agarose Gel ◽

Two Dimensional ◽

Agarose Gel Electrophoresis ◽

Kinetoplast Dna ◽

Gap Filling ◽

Synthesis And Processing ◽

Trypanosoma Equiperdum

Kinetoplast DNA, the mitochondrial DNA in trypanosomes, is a giant network containing topologically interlocked minicircles. Replication occurs on free minicircles that have been detached from the network. In this paper, we report studies on the synthesis and processing of the minicircle L and H strands. Analysis of free minicircles from Trypanosoma equiperdum by two-dimensional agarose gel electrophoresis indicated that elongating L strands are present on theta structures. Hybridization studies indicated that L-strand elongation is continuous and unidirectional, starting near nucleotide 805 and proceeding around the entire minicircle. The theta structures segregate into monomeric progeny minicircles, and those with a newly synthesized L strand have a 8-nucleotide gap between nucleotides 805 and 814 (J. M. Ntambi, T. A. Shapiro, K. A. Ryan, and P. T. Englund, J. Biol. Chem. 261:11890-11895, 1986). These molecules are reattached to the network, where repair of the gap takes place. Of the molecules labeled during a 10-min pulse with [3H]thymidine, gap filling occurred on half within about 15 min and on virtually all by 60 min; however, there was no detectable covalent closure of the newly synthesized L strand by 60 min.

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