Iron targeting to mitochondria in erythroid cells

Prem Ponka, A. D. Sheftel, An-Sheng Zhang

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Immature erythroid cells have an exceptionally high capacity to synthesize haem that is, at least in part, the result of the unique control of iron metabolism in these cells. In erythroid cells the vast majority of Fe released from endosomes must cross both the outer and the inner mitochondrial membranes to reach ferrochelatase, which inserts Fe into protoporphyrin IX. Based on the fact that Fe is specifically targeted into erythroid mitochondria, we have proposed that a transient mitochondria-endosome interaction is involved in Fe transfer to ferrochelatase [Ponka (1997) Blood 89, 1-25]. In this study, we examined whether the inhibition of endosome mobility within erythroid cells would decrease the rate of 59Fe incorporation into haem. We found that, in reticulocytes, the myosin light-chain kinase inhibitor, wortmannin, and the calmodulin antagonist, W-7, caused significant inhibition of 59Fe incorporation from 59Fe-transferrin-labelled endosomes into haem. These results, together with confocal microscopy studies using transferrin and mitochondria labelled by distinct flourescent markers, suggest that, in erythroid cells, endosome mobility, and perhaps their contact with mitochondia, plays an important role in a highly efficient utilization of iron for haem synthesis.

Original languageEnglish (US)
Pages (from-to)735-738
Number of pages4
JournalBiochemical Society Transactions
Volume30
Issue number4
DOIs
StatePublished - Aug 2002
Externally publishedYes

Fingerprint

Erythroid Cells
Mitochondria
Endosomes
Heme
Iron
Ferrochelatase
Transferrin
Mitochondrial Membranes
Myosin-Light-Chain Kinase
Die casting inserts
Confocal microscopy
Calmodulin
Metabolism
Reticulocytes
Blood
Confocal Microscopy
Membranes

Keywords

  • Endosome
  • Haem synthesis
  • Reticulocyte

ASJC Scopus subject areas

  • Biochemistry

Cite this

Iron targeting to mitochondria in erythroid cells. / Ponka, Prem; Sheftel, A. D.; Zhang, An-Sheng.

In: Biochemical Society Transactions, Vol. 30, No. 4, 08.2002, p. 735-738.

Research output: Contribution to journalArticle

Ponka, Prem ; Sheftel, A. D. ; Zhang, An-Sheng. / Iron targeting to mitochondria in erythroid cells. In: Biochemical Society Transactions. 2002 ; Vol. 30, No. 4. pp. 735-738.
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