Metallothionein in Antarctic Fish
157
hamatusMT
ATGGACCCCT GCGACTGCTC CAAAAGTGGG ACCTGCAACT GCGGAGGATC CTGCACTTGC
rastroMT
ATGGATCCCT GTGAGTGCTC CAAAAGTGGG ACCTGCAACT GCGGAGGATC CTGCACTTGC
bernMT
ATGGATCCCT GCGAGTGCTC CAAAAGTGGG ACCTGCAACT GCGGAGGATC CTGCACTTGC
acerMT
ATGGATCCCT GCGAGTGCAC CAAAAGTGGG ACCTGCAACT GCGGAGGATC CTGCACTTGC
***** **** * ** *** * ********** ********** ********** **********
ACAAACTGCT CCTGCACCAG CTGCAAGAAG AGCTGCTGCC CATGCTGCCC ATCCGGCTGC ACCAAATGCG
ACAAACTGCT CCTGCACCAG CTGCAAGAAG AGCTGCTGCC CATGCTGCCC ATCCGGCTGC ACCAAATGCG
ACAAACTGCT CTTGCACCAG TTGCAAGAAG AGCTGCTGCC CATGCTGCCC ATCCGGCTGC ACCAAATGCG
ACAAACTGCT CCTGCACCAG CTGCAAGAAG AGCTGCTGCC CATGCTGCCC ATCCGGCTGC ACCAAATGCG
********** * ******** ********* ********** ********** ********** **********
CCTCTGGCTG CGTGTGCAAA GGGAAGACTT GTGACACAAG CTGCTGTCAG TGAAG ..... GACCTCAGCC
CCTCTGGCTG CGTGTGCAAA GGGAAGACTT GTGACACAAG CTGCTGTCAG TGAA ...... GACCTCAG.C
CCTCTGGCTG TGTGTGCAAA GGGAAGACTT GTGACACAAG TTGCTGTCAG TGAAGAGCCT GACCTCCAGT
CCTCTGGCTG CGTGTGCAAA GGGAAGACTT GTGACACAAG CTGCTGTCAG TGAAGAAC . . . . . . . TCAGC
**********
********* ********** **********
*********
CGCTTCTGCT CTTGGAATGG AGCCTTTGTG AACTACTTTG ACTACATTCC TAGTTGCAAA TGTCTACAGA
CGCTTCTGCT CTTGGAATGG AGCCTTTGTG AACTACTTTG ACTACATTCC T.GTTGCAAA TGTCTACAGA
CGCTTCTGCT CTTGGAATGG AGCCTTTGTG AACTACTTTA ACTACATTCC T.GTTGCCAA TGTCTACAGA
CGCTTCTGCT CTTGGAATGG AGCCTTTGTG AACTACTTTG AATACATTCC TGCTTCTGCT CTTGGAATGG
********** ********** ********** *********
* ******** * **
GAATGGTG . . . . . . AA.TTG TGTACTTGTT TACG.ATGTT GAAATAAATG CACTTCCTTG
....... G . . . . . . AA.TTG TGTACTTGTT TACG.ATGTT GAAATAAATG CAGTTACTTG
GAATGGTG . . . . . . AATTTT TGTACTTGTT TATGAATGTT GAAATAAATA CAGTTCCTTG
AGCCTTTGTG AACTACTTTG AATACATTCC TTACTATGTT GAAATAAATG CAGTTCCTTG
***** ********* ** ** ****
Fig. 5. Aligned nucleotide sequences of MTs from C. aceratus, C. hamatus, C.
rastrospinosus and T bernacchii
In order to obtain information on the 5'-UTRs, a 5'-RACE protocol was
applied using a 5'-Marathon cDNA amplification kit and the fish MTspecific primer (5 '-GCAGGAGCAGTTTGTGCAAGTGCA-3'). The
amplified fragments were cloned as usual in the pGEM-T vector and
sequenced. As shown in Fig. 6, the leader sequence of the T bernacchii
MT mRNA lacks the initial segment of 21 nucleotides present in the
icefish MT mRNA; in addition, a mismatching segment is found 42
nucleotides upstream of the AUG codon.
1
hamat GACAACACAACACGCUCUCAUCUGAGACCAGAUACACUGCACCUACUCACGAGGACGAGAGACAUCACCUG
II 11111
I 11111111111111111111111 11111111111111
bern
CUCAGACCGAAGACACUGCACCUACUCACGAGGACAAGAGACAUCACCUG
94
AGAACAUGGACCCCUGCGACUGC
1111111111111 III I III
AGAACAUGGACCCUUGCCAGUGC
73
Fig. 6. Sequences of the 5' noncoding regions (5'-UTR) of MT mRNAs from C. hamatus
and T bernacchii