Ferritin in Chlamydomonas reinhardtii
Ferritin is a key enzyme in maintaining iron homeostasis. In vertebrates, it is a multimetric protein consisting of both heavy (H, 21 kDa) and light (L, 19 kDa) subunits with iron stored as ferric oxyhydroxide Fe(III)OOH. In plants, however, there is only one protein which is most closely related to the H subunit but has similarities to the L subunit. The pre-protein has a plastid specific N-terminus sequence that targets the protein to the chloroplasts, proplastids, etioplasts, chromoplasts, and amyloplasts. Ferritin consists of 24 subunits arranged in compact shape of 4.3.2 symmetry. In A. thaliana there are multiple ferritin genes, but the following sequence probably represents a single ferritin gene in C. reinhardtii.
-56 ATGCATACGAGGTCTAGAATTTCGGGCGCTTGGCGTTGTCCTTACCAAGTCACGTA
+1 ATGGCGCTCTGTGCTCGCGTTTTCGGGGCCCCGGCCAAGCTGGCGAAGCAGCAGGTGGTT
M A L C A R
V F G A P A K L A K Q
Q V V
+61 ACCCCCCGGCGCACTTCGGCCCCTCGCGCTGTGGCGCGCCATGCCACTGTGGACAAGATC
T P R R T
S A P R A V A R H A T
V D K I
+121 ACTGGCATTGTTGTTCAGCCTGCCGTTCAGTTCTCGGAGGTGCAGAGCGAGCTGGCGACC
T G I V V
Q P A V Q F S E V Q
S E L A T
+181 GTGGATAAGACCAACCAGAACATCCAGTCGCTGGCGCGCGTTGACTTCCACCCAGCCTGC
V D K T N Q
N I Q S L A R V D F H
P A C
+241 GAGGCCGCCATCAACGAGCAGGTCAACATCGAGTACAACGTGTCTTACCTGTACCACGCG
E A A I N
E Q V N I E Y N V S
Y L Y H A
+301 CTGTGGGCCTACTTCGACCGCGACAACGTGGCGCTGCCCGGCCTGGCCGCCTTCTTCAAG
L W A Y F
D R D N V A L P G L A
A F F K
+361 GCCGGCAGCGAGGAGGAGCGCGAGCACGCAGAGCTGCTCATGGAGTACCAGAACCGTCGC
A G S E E E
R E H A E L L M E
Y Q N R R
+421 GGCGGCCGCGTTGTGCTGGGCGCCATCTCCATGCCGGACCTGGACCTCAGCGCCAGCGAG
G G R V V L
G A I S M P D L D
L S A S E
+481 AAGGGCGATGCGCTGTACGCCATGGAGCTGGCCCTGAGCCTGGAGAAGCTCAACTTCCAG
K G D A L
Y A M E L A L S L E
K L N F Q
+541 AAGCTGCGCCAGCTGCACTCGGTGGCGGACGAGCACGGCGATGCCTCCATGGCCGACTTC
K L R Q L
H S V A D E H G D A
S M A D F
+601 GTGGAGGGCGAGCTGCTGAACGAGCAGTTGAGGCTGTGAAGAAGGTGTCCGAGTACGTGT
V E G E L
L N E Q L R L *
+661 CGCAGCTGCGGCGGGTGGGCCAGGGCCTGGGCGTGTACCAGTTTGACAAGCAGCTGGCCG
+721 CCGAGGTGGCCGCCGGCGCCGCCGCGTAAAGGGAGTGGTCGCGTAGCGAGCAGACAGCTC
+781 GGTTGGTTGAGATGGGGGTGAAGAACATGTGAGGGCACAGCTCAGCATGTGATTCTGCGG
+841 GGGGCCATGCAACTCGGCAGTTGATCTTGTAGATTGCGAAGGCGTAGCGTATATGTTGTG
+901 ATCAATTGCAAAGTGTGTGTGGGCATGGCCTTGAAGTAGAATGTGCTTTCTCCTTCCCGT
+961 CGGCGGAGGACTGATCGTGCGCGCGAGGTTGTTTCGCTCGTGCTTCTGATTGTGCACATG
+1021 AGTAACAGGGGTGGAACGGGAGTGTTTCGTGTCGGCATTCGACCTGAAGCACGGCCCCTG
+1081 GACCATACGCGTGACCTGCCGGACCATGACAGGACGCCAAGGGCCGAGTACGCATGCAGT
+1141 GCTTTTTTTGGGTGGCGATGGGTGGCAACGGATAGGATGCTCTTAAATGTGGCGAGAGGA
+1201 GGTGATATGCGATGCAGTCTGGGTGCGCCCTGCGCGGGGTGTATCAGGGGAGGTATCCTC
+1261 GCGGCTACCAGAGCACTTCCCTGCGCTGATCTGTGAATTCCGGGAGGGACCCCAGCGCCC
+1321 TCCCAACCCATGTAAGAAGATCATGCGTCCAAAAAA