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Controlling iron/oxygen chemistry in biology depends on multiple genes, regulatory messenger RNA (mRNA) structures, signaling
pathways and protein catalysts. Ferritin, a protein nanocage around an iron/oxy mineral, centralizes the control. Complementary
DNA (antioxidant responsive element/Maf recognition element) and mRNA (iron responsive element) responses regulate ferritin
synthesis rates. Multiple iron-protein interactions control iron and oxygen substrate movement through the protein cage, from
dynamic gated pores to catalytic sites related to di-iron oxygenase cofactor sites. Maxi-ferritins concentrate iron for the
bio-synthesis of iron/heme proteins, trapping oxygen; bacterial mini-ferritins, DNA protection during starvation proteins,
reverse the substrate roles, destroying oxidants, trapping iron and protecting DNA. Ferritin is nature’s unique and conserved
approach to controlled, safe use of iron and oxygen, with protein synthesis in animals adjusted by dual, genetic DNA and mRNA
sequences that selectively respond to iron or oxidant signals and link ferritin to proteins of iron, oxygen and antioxidant
metabolism.
Received 25 June 2005; received after revision 17 October 2005; accepted 25 November 2005 相似文献
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K. L. Hintze Ann Baker Grow L. J. Fischer 《Cellular and molecular life sciences : CMLS》1977,33(11):1495-1497
Summary Hypophysectomized rats given cyproheptadine (40 mg/kg) for 10 days exhibited a loss of pancreatic immunoreactive insulin and ultrastructural changes in the cytoplasm of beta-cells. Sham-operated animals given cyproheptadine showed identical changes in pancreatic beta-cells except that cytoplasmic involvement progressed to the formation of large vacuoles. The pituitary is not directly involved with the cyproheptadine-induced depletion of pancreatic insulin but plays a role in the formation of large cytoplasmic vacuoles.Acknowledgments. This work was supported by U. S. Public Health Service, grant GM 12675. 相似文献
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