Rescue of embryonic lethality in reduced folate carrier-deficient mice by maternal folic acid supplementation reveals early neonatal failure of hematopoietic organs.
The reduced folate carrier (RFC1) is an important route by which the major blood folate, 5-methyltetrahydrofolate, is transported into mammalian cells. In this study we determined the consequences of inactivation of RFC1 in mice by homologous recombination. While RFC1-null embryos died in utero before embryonic day 9.5 (E9.5), near-normal development could be sustained in RFC1(-)/- embryos examined at E18.5 by supplementation of pregnant RFC1(+/-) dams with 1-mg daily subcutaneous doses of folic acid. About 10% of these animals went on to live birth but died within 12 days. These RFC1(-)/- mice showed a marked absence of erythropoiesis in bone marrow, spleen, and liver along with lymphoid depletion in the splenic white pulp and thymus. In addition, there was some impairment of renal and seminiferous tubule development. These data indicate that in the absence of RFC1 function, neonatal animals die due to failure of hematopoietic organs.
Zhao
R
R
Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Russell
R G
RG
Wang
Y
Y
Liu
L
L
Gao
F
F
Kneitz
B
B
Edelmann
W
W
Goldman
I D
ID
D000483:Alleles; D000818:Animals; D015153:Blotting, Western; D001853:Bone Marrow / Q000196:embryology / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics* / Q000502:physiology*; D003433:Crosses, Genetic; D019587:Dietary Supplements; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005313:Fetal Death; D005492:Folic Acid / Q000378:metabolism* / Q000627:therapeutic use*; D005822:Genetic Vectors; D005838:Genotype; D006410:Hematopoiesis; D008099:Liver / Q000196:embryology / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000502:physiology*; D026901:Membrane Transport Proteins; D008727:Methotrexate / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D011995:Recombination, Genetic; D013154:Spleen / Q000196:embryology / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology; D013763:Tetrahydrofolates / Q000378:metabolism; D013950:Thymus Gland / Q000196:embryology; D013997:Time Factors
D002352:Carrier Proteins; D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C492292:Slc19a2 protein, mouse; D013763:Tetrahydrofolates; D005492:Folic Acid; C005984:5-methyltetrahydrofolate; D008727:Methotrexate