Isolation of the catalytic core of DNA polymerase alpha from rabbit bone marrow

The activities of 5-methyltetrahydrofolate (5-CH3THF) related enzymes and DNA polymerase alpha were determined in bone marrow cells obtained from patients with vitamin B12 deficient megaloblastic anemia and compared with those from healthy volunteers and patients with hemolytic anemia. 5-CH3THF homocysteine methyltransferase activity was significantly lower than that in the control subjects. 5,10- methylenetetrahydrofolate reductase activity was only slightly elevated to that in the control subjects. DNA polymerase alpha activity was significantly higher than that in the control. High deoxyuridine suppression test values in vitamin B12 deficient bone marrow cells were improved by tetrahydrofolate, but not by 5-CH3THF. These data indicate that, even though the reverse reaction catalyzed by 5,10- methylenetetrahydrofolate reductase may be operative in vitamin B12 deficiency, it is not sufficient to correct the disturbance in folate metabolism in vitamin B12 deficiency. Increased DNA polymerase alpha activity may be due to compensation for disarranged DNA synthesis.

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5-Methyltetrahydrofolate related enzymes and DNA polymerase alpha activities in bone marrow cells from patients with vitamin B12 deficient megaloblastic anemia

Blood ◽

10.1182/blood.v59.4.832.832 ◽

1982 ◽

Vol 59 (4) ◽

pp. 832-837 ◽

Cited By ~ 8

Author(s):

Y Kano ◽

S Sakamoto ◽

K Hida ◽

K Suda ◽

F Takaku

Keyword(s):

Bone Marrow ◽

Vitamin B12 ◽

Dna Polymerase ◽

Methylenetetrahydrofolate Reductase ◽

Bone Marrow Cells ◽

Megaloblastic Anemia ◽

Vitamin B12 Deficiency ◽

Dna Polymerase Alpha ◽

B12 Deficiency ◽

Marrow Cells

Abstract The activities of 5-methyltetrahydrofolate (5-CH3THF) related enzymes and DNA polymerase alpha were determined in bone marrow cells obtained from patients with vitamin B12 deficient megaloblastic anemia and compared with those from healthy volunteers and patients with hemolytic anemia. 5-CH3THF homocysteine methyltransferase activity was significantly lower than that in the control subjects. 5,10- methylenetetrahydrofolate reductase activity was only slightly elevated to that in the control subjects. DNA polymerase alpha activity was significantly higher than that in the control. High deoxyuridine suppression test values in vitamin B12 deficient bone marrow cells were improved by tetrahydrofolate, but not by 5-CH3THF. These data indicate that, even though the reverse reaction catalyzed by 5,10- methylenetetrahydrofolate reductase may be operative in vitamin B12 deficiency, it is not sufficient to correct the disturbance in folate metabolism in vitamin B12 deficiency. Increased DNA polymerase alpha activity may be due to compensation for disarranged DNA synthesis.

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PCNA-dependent DNA polymerase .delta. from rabbit bone marrow

Biochemistry ◽

10.1021/bi00164a015 ◽

1992 ◽

Vol 31 (49) ◽

pp. 12403-12409 ◽

Cited By ~ 5

Author(s):

Changde Lu ◽

John J. Byrnes

Keyword(s):

Bone Marrow ◽

Dna Polymerase ◽

Dna Polymerase Delta ◽

Rabbit Bone

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The structure of pre-mRNA and mRNA from erythroid cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082030 ◽

1978 ◽

Vol 36 (2) ◽

pp. 234-235

Author(s):

A.-M. Ladhoff ◽

B.J. Thiele ◽

Ch. Coutelle ◽

S. Rosenthal

Keyword(s):

Bone Marrow ◽

Structural Transformation ◽

Electron Micrographs ◽

Ammonium Acetate ◽

Bone Marrow Cells ◽

Erythroid Cells ◽

Globin Mrna ◽

Ordered Structures ◽

Rabbit Bone ◽

Rabbit Reticulocytes

The suggested precursor-product relationship between the nuclear pre-mRNA and the cytoplasmic mRNA has created increased interest also in the structure of these RNA species. Previously we have been published electron micrographs of individual pre-mRNA molecules from erythroid cells. An intersting observation was the appearance of a contour, probably corresponding to higher ordered structures, on one end of 10 % of the pre-mRNA molecules from erythroid rabbit bone marrow cells (Fig. 1A). A virtual similar contour was observed in molecules of 9S globin mRNA from rabbit reticulocytes (Fig. 1B). A structural transformation in a linear contour occurs if the RNA is heated for 10 min to 90°C in the presence of 80 % formamide. This structural transformation is reversible when the denatured RNA is precipitated and redissolved in 0.2 M ammonium acetate.

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