Role of folate binding proteins in folate metabolism.
The essential role of folates in cellular biochemistry is well established, but the nature of the participation by folate-binding proteins has been disputed. This review will define folate-binding proteins and distinguish them from low-affinity, nonspecific folate binders and folate-dependent intracellular enzymes. We outline changes in plasma folate-binding proteins in various clinical states, review their postulated functions, detail the biochemistry of mammalian soluble folate-binding proteins and their membrane-bound immunologically cross-reactive possible precursors, and present evidence that the latter proteins may function as the physiologic folate receptors and intracellular regulators of folate coenzyme availability.
Kane
M A
MA
Medical Oncology Section, Denver Veterans Administration Medical Center, Colorado.
Waxman
S
S
D000818:Animals; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D003429:Cross Reactions; D058973:Folate Receptors, GPI-Anchored; D005492:Folic Acid / Q000378:metabolism*; D006801:Humans; D011498:Protein Precursors / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D011956:Receptors, Cell Surface
D002352:Carrier Proteins; D058973:Folate Receptors, GPI-Anchored; D011498:Protein Precursors; D011956:Receptors, Cell Surface; D005492:Folic Acid