Thyroglobulin
I
I
Tyr
3,5,3¹5¹-tetraiodothyronine
I
I
Tyr
I
I
I
Tyr
O
T
CH2CHCOOH
I
I
I
Tyr
NH2
+
NH2
I
4
I
I
Tyr
CH2CHCOOH
NH2
CH2CHCOOH
3,3¹,5¹-Triiodothyronine (reverse T3)
NH2
Tyr
I
I
I
Tyr
O
rT3
I
3,5,3¹-Triiodothyronine (T3)
I
I
Tyr
I
I
I
Tyr
O
T4
I
T3
Tyr
I
I
I
Tyr
O
I
5¹- deiodination
5-deiodination
CH2CHCOOH
³ACTIVATION² PATHWAY
³DEACTIVATION² PATHWAY
NH2
STEP 3 DEIODINATION
SELENODEIODINASES