Iron Transport

Question 1

Heme Carrier Protein 1 (HCP1)/ Heme Tranporter (HT)

Answer 1

Transports iron into enterocytes

Question 2

Heme Oxygenase 1 (HO1)

Answer 2

Enzyme needed for iron to be released from heme

Question 3

NON-HEME IRON STATE

Answer 3

FEERIC

Question 4

DUODENAL CYTOCHROME B (DCTYB)

Answer 4

⚡️Reduces ferric into ferrous for absorption

⚡️Contains FERRIC REDUCTASE ENZYME

⚡️ Co-factor: VITAMIN C

Question 5

DIVALENT METAL TRANSPORTER 1

Answer 5

Absorbs iron to enterocyte (Non-Heme)

Question 6

FERRITIN

Answer 6

⚡️Form of Iron if iron level is high in blood

Question 7

FERROPORTIN (FPN)

Answer 7

Transporter that moves iron in the blood if iron level is low

⚡️Downregulated bu HEPCIDIN (HP)

Question 8

HEPCIDIN (HP)

Answer 8

⚡️Master-regulator of iron
⚡️Down-regulator of ferroportin
⚡️Encoded by HAMP gene
⚡️25 aa
⚡️Hemojuvelin

Question 9

HAPHAESTIN (FERROUS OXIDASE)

Answer 9

⚡️Contains ferrous oxidase
⚡️Reoxidize ferrous to ferric form for ferrous to bind with transferrin
⚡️Copper-dependent

Question 10

Copper

Answer 10

Needed by haphaestin for iron to be reoxidized

Question 11

Iron Transferrin Complex (FeTF)

Answer 11

⚡️Iron bound to transferrin

⚡️Binds with TRANSFERRIN RECEPTOR (TfR)

Question 12

Liver-iron pool (LIP)

Answer 12

Pool of iron which are weakly-bound

Question 13

Sources of iron in the liver

Answer 13

1. Membrane – Transferrin bound

2. Luminal bound – Non-transferrin bound

Question 14

What happens to transferrin once iron is released into the endosome?

Answer 14

APOTRANSFERRIN

— still binds into the receptor and goes out again into the circulation

Question 15

How can iron dissociate from transferrin?

Answer 15

Endosome or lysosome should have an acidic pH