Plant Molecular Biology 18: 611-612, 1992. © 1992 Kluwer Academic Publishers. Printed in Belgium.
611
Update section Sequence
Isolation and nucleotide sequence of a cDNA clone encoding the beta subunit of mitochondrial ATP synthase from Hevea brasiliensis Mee-Len Chye and Chio-Tee Tan Institute of Molecular and Cell Biology, National University of Singapore, Singapore 0511, Republic of Singapore Received 24 September 1991; accepted 2 October 1991
The F~Fo ATP synthase complex, which is essential in the synthesis of ATP, is found in the membranes of bacteria, chloroplasts and mitochondria. It consists of a n F 1 soluble component and an Fo integral membrane protein complex. The F 1 ATP synthase component which comprises five subunits (a, fl, ~, b and e) contains the catalytic site of the enzyme [4, 11]. The F 0 integral membrane portion comprises three subunits in Escherichia coli, four subunits in chloroplast and ten subunits in mitochondria [6]. In E. coli, the uric operon encodes the entire FIFo ATP synthase complex [3, 5, 9] while in higher plants this complex is encoded by both mitochondrial and nuclear genes. Of all the FI subunits the fl subunit is known to be the most conserved [6]. In higher plants the B subunit of c h l o r o p l a s t F I ATP synthase is encoded by the chloroplast genome [10, 12] while that of mitochondrial FI ATP synthase is nuclear-encoded [1]. Here we report the cloning of a c D N A encoding the fl subunit of mitochondrial ATP synthase in Hevea brasiliensis (rubber). We used atp2-1, a genomic clone encoding the fl subunit of mitochondrial ATP synthase from Nicotiana plumbaginifolia [ 1 ], as probe to screen a Hevea 2gtl 1 leaf c D N A library [2] by in situ plaque hybridization. Several putative positive clones were obtained and the longest of these clones was sequenced.
This c D N A contains 21 bp of 5'-untranslated region, 1686 bp of coding region, 314 bp of 3'untranslated region and a poly(A) tail (Fig. 1). A potential polyadenylation signal is present upstream from the poly(A) tail (Fig. 1). Analysis of the c D N A sequence surrounding the initiation codon, A C C A A T G G C , showed a high conservation in nucleotides with that of the consensus sequence reported for plants, A A C A A T G G C [ 7 ]. The coding region contains an open reading frame of 562 amino acids which would encode a protein of Mr 60 265. Comparison of the Hevea c D N A with that of tobacco atp2-1 shows 80.1~o nucleotide homology. When their deduced amino acid sequences were compared there was 86.7~o homology and amino acids at the carboxy termini were highly conserved. A mitochondrial targeting sequence is present at the amino terminus of the fl subunit of mitochondrial ATP synthase from Hevea. Eleven out of the first twelve amino acids in the Hevea polypeptide are identical to that of tobacco and these residues are likely to be involved in mitochondrial targeting. As in the analysis of other mitochondrial targeting sequences [8], the first forty residues of the Hevea polypeptide are enriched in serine (17 residues), arginine (5 residues) and leucine (5 residues), and lack aspartic acid and glutamic acid residues. Northern blot analysis using total R N A pre-
The nucleotide sequence data reported will appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession number X58498.
612 CTCTCTTT~GCCCC~CC~TGGCTTCACGCAGACTATTATCCTCTCTTCTCCC~TCA m a s r r l l s s l l r s . . . . . . . . a . . . q TC~GTCGCC~TCAGTCTCC~TCTCCTATCTC~CATC~CCCT~GCTTTCTTCC s s r r s v s k s p i s n l n p k l s s . a q . g g g l i s - r s l g n s i p k TCATCTCCATCCTCT~GAGCCGCGCGTCTCCTTAT~TTACCTCCTCACACGCGCGGCT s
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360
TT~CG~TCTTGA~TTTTG~CCATTC~TCAGGCTAGTGCT~AGGTGGCTCAGCAC i t s l e v l d h s i r l v l e v a q h 1 3 3 . . a . . . . . nq . . . . . . . . . . AT~GT~GGGTAT~TTAGGACCATTGCCATGGAT~GACTG~GGTTTGGTGA~GGG m g e g m v r t i a m d g t e q l v r g ] 5 3 1 . . n CA~GCGTCCTC~TACTGGGTCTCCCATTACAGTGCCAGTGGGTAGG~C~CCCTTGG q r v l n t g s p i t v p v g r a n p w 1 7 3 . . . . . . r . . . . . . . . . . t 1 g ACGTATCATG~GTCATTGGA~GC~TTGAC~GAGGGGTGATATC~GACCA~CAC t y h e v i g e p i d e r g d i k t s h 1 9 3 r i i n a p. t. d. TTCTTGCCCATTCACAGA~TCCAGCTTTTGTT~TC~GC~CT~GC~CAGATT
420
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480
540
600
.
a
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q
q
i
2
1
660
3
. . . . . . . . . . . . e . . . . . . . CTTGT~CTGGTATC~GGTTGTTGATCTTCTT~ACCATACC~GG~AGG~GATT i v t g i k v v d l l a p y q r g g k i 2 3 3
720
GG~TGTTTGGTGGTGCT~TGTAGGAAAAACTGTGCTTATTATGG~CTTATAAAC~T g l f g q a q v g k t v l l m e l l n n 2 5 3
780
GTTGCAAAAGCTCACGGTGGTTTTTCAGTGTTT~T~TGTTGGAGAGCGCACTCGTGAG v a k a h g g f s v f a g v g e r t r e 2 7 3
840
GGT~T~CCTGTACAGAGAAATGATTGAGAGT~TGTCATT~GCTA~GGAT~GCAG g n d l y r e m i e s g v i k l g d k q 2 9 3 . . . . . . . . . . . . a . . . . e . . GCT~CAGC~TGCGCCCTTGTATATGGTCAAATG~TG~CCCCCTGGTGCTCGTGCC a d s k c a l v y g q m n e p p g a r a 3 1 3 s e . . . . . . . . . . . . . . . . . . CGTGTT~TCT~CTGGGC~CTGTGGCTGAGCACTTCCGTGATGCT~GGAC~GAT r v g l t g l t v a e h f r d a e g q d 3 3 3
900
96~
1020
G T ~ T T C T C T T C A T T G A C ~ T A T T T T C C G C T T C A C C C A G G C T ~ T T C A ~ G G T G T C T G C T 1080 v l l f l d n J f r f t q a n s e v s a 3 5 3 T T ~ T T ~ T C G T A T C C C A T C T G C T G T C G G T T A C C ~ C C A A C T T T G G C T A C T G A T C T G G G A ]140 l l g r i p s a v g y q p t l a t d l g 3 7 3
GGTCTCC~GAGCGTATTAC~CCACC~GAAA~TTCTATCACTTCTGTCCAGGCTATA]200 g
l
q
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1
3
9
3
TATGTGCCTGCTGATGACTTGACTGATCCTGCACCT~TAC~CCTTT~ACACTTGGAT ]260 y v p a d d l t d p a p a t t f a h l d 4 1 3 GCCAC~CTGTGTTGTCACGACAGATTTCTGAGCTG~TATCTATCCT~TGTTGATCCC 1320 a t t v l s r q i s e l g i y p a v d p 4 3 3 CTTGATTCTACATCTCGTATGCTCTCTCCTCATATTTTGGGTGAGG~CACTAC~TACT 1380 l d s t s r m l s p h i ] . q e e h y n t 4 5 3 . . . . . . . . . . . . . . . d . . . . GCTCGT~AGTGCAAAAGGTTCTTCAG~CTAC~G~TCTGC~GATATTATTGCCATTI440 a r g v q k v l q n y k n l , q d i i a i 4 7 3 TT~G~TGGATGA~TTAGTC~GATGAC~GTTGACAGTTGCCCGAGCACGG~ATCI500 i g m d e l s e d d k l t v a r a r k i , 493 . . . . . . . . . . . m . . . . . . . . CA~GG~CTTGAGCCAGCCTTTCCATGTTGCA~GTTTTCACAGGT~CCCTG~GI560 q r f l s q p f h v a e v f t g a p g k S l 3 TATGTT~GTTG~GAGAGCAT~CCAGCTTCCAG~TGTGTT~AT~AAAATATGAT 1620 y v e l k e s l t s f q g v l d g k y d 5 3 3 • . d . . . . . n . . . . . . . . . . . G A ~ T T C C A G ~ C A G T C A T T T T A C A T G G T T G G A G G C A T T G A T G A ~ T G A T A G C C ~ G G C C 1680 d l p e q s f y m v g g i d e v i a k a 5 5 3 .. s . . . . . . . . . . . . . . . ~ T ~ G A T T G C A A A G G A G T C A ~ A T C C T ~ C A G A A A C G G ~ C T C T C T C T G C A G T C T T T T 1740 d
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. . . . . . .
References
k
GTTTGT~GGTGATTGGT~CGTTGTGGATGTGAGGTTCGATGAGGGACTGCCTCCGATT v c q v i g a v v d v r f d e g l p p i l 1 3
.
pared from leaf and laticifer showed that the c D N A encoding the fl subunit of mitochondrial ATP synthase from Hevea hybridized to a 2.1 kb transcript in both cases.
240 73
e
q . . . . . . . p , s q p s t . p . s GGTG~GG~GGTGGT~TTACT~TGAGTTCACTGGAAAGGGT~GATTG~CAG g g k g g g k l t d e f t g k g a i g q •
120 33
v
~GTAC~GA~TCCGCCGCC~CGCTGCCCCACCTC~CCTCCTCCA~G~GCCCGAG e
60 13
s
1. Boutry M, Chua N-H: A nuclear gene encoding the beta subunit of the mitochondrial ATP synthase in Nicotiana plurnbaginifolia. EMBO J 4:2159-2165 (1985). 2. Chye M-L, Kush A, Tan C-T, Chua N-H: Characterisation of c D N A and genomic clones encoding 3-hydroxy3-methylglutaryl-coenzyme A reductase from Hevea brasiliensis. Plant Mol Biol 16:567-57 (1991). 3. Downie JA, Gibson F, Cox GB: Membrane adenosine triphosphatases of prokaryotic cells. Annu Rev Biochem 48:103-131 (1979). 4. Futai M: Reconstitution of ATPase activity from the isolated ~, fl and 7 subunits of the coupling factor, F 1, of Escherichia coll. Biochem Biophys Res Comm 79: 12311237 (1977). 5. Futai M, Kanazawa H: Structure and function ofprotontranslocating adenosine triphosphatase (FoF l ): biochemical and molecular biological approaches. Microbiol Rev 47:285-312 (1983). 6. Futai M, Takato N, Maeda M: ATP synthase (H +ATPase): results by combined biochemical and molecular biological approaches. Annu Rev Biochem 58:111136 (1989). 7. Lutcke HA, Chow KC, Mickel FS, Moss KA, Kern HF, Scheele GA: Selection of A U G initiation codons differ in plants and animals. EMBO J 6:43-48 (1987). 8. von Heijne G: Mitochondrial targeting sequences may form amphiphilic helices. EMBO J 5:1335-1342 (1986). 9. Walker JE, Saraste M, Gay NJ: The unc operon. Nucleotide sequence, regulation and structure of ATP-synthase. Biochim Biophys Acta 768:164-200 (1984). 10. Westhoff P, Nelson N, Bunemann H, Herrmann RG: Localization of genes for coupling factor subunits on the spinach plastid chromosome. Curr Genet 4 : 1 0 9 - 1 2 0 (1981). 11. Yoshida M, Okamoto H, Sone N, Hirata H, Kagawa Y: Reconstitution ofthermostable ATPase capable of energy coupling from its purified subunits. Proc Natl Acad Sci U S A 74:936-940 (1977). 12. Zurawski G, Bottomley W, Whitfield PR: Structures of the genes for the fl and e subunits of spinach chloroplast ATPase indicate a dicistronic m R N A and an overlapping stop/start signal. Proc Natl Acad Sci U S A 79: 62606264 (1982).
562
a
GTTCTCTTGTCCGGAAAATTGCAG~TCAAAAAT~TCTAGGT~TGCTGGCAACAGGA
1800 TATTATTGATTTTTTTGAGGTGAAATGTGTTGGATTATG~TTCCCGTTTTAATGTGTTA 1860 T T ~ A G A G T G T G A T ~ T A T A G ~ C A G G G G A C T G C C C T G C C T G C C ~ G C C C C T C T T T T T T C 1920 TTTTTATTTATTT~T~GGGGAAAAAGAAAGGCGGG~TGTATATTTTTCCTTTTCTAT 1980 2021 TTT~T~CCT~G~CATGAAACGTGACCATTTTCACTTG(A)n
Fig. 1. Nucleotide sequence and deduced amino acid sequence of a c D N A clone encoding the beta subunit of mitochondrial ATP synthase from Hevea brasiliensis. The deduced
amino acid sequence is shown below the nucleotide sequence of its cDNA. The deduced amino acid of tobacco atp2-1 is compared with that ofHevea atp2; identical amino acids in the two atp2 polypeptides are denoted by dots, and mismatches are shown below the Hevea atp2 amino acid sequence. A potential polyadenylation site is underlined•
611
Update section Sequence
Isolation and nucleotide sequence of a cDNA clone encoding the beta subunit of mitochondrial ATP synthase from Hevea brasiliensis Mee-Len Chye and Chio-Tee Tan Institute of Molecular and Cell Biology, National University of Singapore, Singapore 0511, Republic of Singapore Received 24 September 1991; accepted 2 October 1991
The F~Fo ATP synthase complex, which is essential in the synthesis of ATP, is found in the membranes of bacteria, chloroplasts and mitochondria. It consists of a n F 1 soluble component and an Fo integral membrane protein complex. The F 1 ATP synthase component which comprises five subunits (a, fl, ~, b and e) contains the catalytic site of the enzyme [4, 11]. The F 0 integral membrane portion comprises three subunits in Escherichia coli, four subunits in chloroplast and ten subunits in mitochondria [6]. In E. coli, the uric operon encodes the entire FIFo ATP synthase complex [3, 5, 9] while in higher plants this complex is encoded by both mitochondrial and nuclear genes. Of all the FI subunits the fl subunit is known to be the most conserved [6]. In higher plants the B subunit of c h l o r o p l a s t F I ATP synthase is encoded by the chloroplast genome [10, 12] while that of mitochondrial FI ATP synthase is nuclear-encoded [1]. Here we report the cloning of a c D N A encoding the fl subunit of mitochondrial ATP synthase in Hevea brasiliensis (rubber). We used atp2-1, a genomic clone encoding the fl subunit of mitochondrial ATP synthase from Nicotiana plumbaginifolia [ 1 ], as probe to screen a Hevea 2gtl 1 leaf c D N A library [2] by in situ plaque hybridization. Several putative positive clones were obtained and the longest of these clones was sequenced.
This c D N A contains 21 bp of 5'-untranslated region, 1686 bp of coding region, 314 bp of 3'untranslated region and a poly(A) tail (Fig. 1). A potential polyadenylation signal is present upstream from the poly(A) tail (Fig. 1). Analysis of the c D N A sequence surrounding the initiation codon, A C C A A T G G C , showed a high conservation in nucleotides with that of the consensus sequence reported for plants, A A C A A T G G C [ 7 ]. The coding region contains an open reading frame of 562 amino acids which would encode a protein of Mr 60 265. Comparison of the Hevea c D N A with that of tobacco atp2-1 shows 80.1~o nucleotide homology. When their deduced amino acid sequences were compared there was 86.7~o homology and amino acids at the carboxy termini were highly conserved. A mitochondrial targeting sequence is present at the amino terminus of the fl subunit of mitochondrial ATP synthase from Hevea. Eleven out of the first twelve amino acids in the Hevea polypeptide are identical to that of tobacco and these residues are likely to be involved in mitochondrial targeting. As in the analysis of other mitochondrial targeting sequences [8], the first forty residues of the Hevea polypeptide are enriched in serine (17 residues), arginine (5 residues) and leucine (5 residues), and lack aspartic acid and glutamic acid residues. Northern blot analysis using total R N A pre-
The nucleotide sequence data reported will appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession number X58498.
612 CTCTCTTT~GCCCC~CC~TGGCTTCACGCAGACTATTATCCTCTCTTCTCCC~TCA m a s r r l l s s l l r s . . . . . . . . a . . . q TC~GTCGCC~TCAGTCTCC~TCTCCTATCTC~CATC~CCCT~GCTTTCTTCC s s r r s v s k s p i s n l n p k l s s . a q . g g g l i s - r s l g n s i p k TCATCTCCATCCTCT~GAGCCGCGCGTCTCCTTAT~TTACCTCCTCACACGCGCGGCT s
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TT~CG~TCTTGA~TTTTG~CCATTC~TCAGGCTAGTGCT~AGGTGGCTCAGCAC i t s l e v l d h s i r l v l e v a q h 1 3 3 . . a . . . . . nq . . . . . . . . . . AT~GT~GGGTAT~TTAGGACCATTGCCATGGAT~GACTG~GGTTTGGTGA~GGG m g e g m v r t i a m d g t e q l v r g ] 5 3 1 . . n CA~GCGTCCTC~TACTGGGTCTCCCATTACAGTGCCAGTGGGTAGG~C~CCCTTGG q r v l n t g s p i t v p v g r a n p w 1 7 3 . . . . . . r . . . . . . . . . . t 1 g ACGTATCATG~GTCATTGGA~GC~TTGAC~GAGGGGTGATATC~GACCA~CAC t y h e v i g e p i d e r g d i k t s h 1 9 3 r i i n a p. t. d. TTCTTGCCCATTCACAGA~TCCAGCTTTTGTT~TC~GC~CT~GC~CAGATT
420
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480
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600
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2
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660
3
. . . . . . . . . . . . e . . . . . . . CTTGT~CTGGTATC~GGTTGTTGATCTTCTT~ACCATACC~GG~AGG~GATT i v t g i k v v d l l a p y q r g g k i 2 3 3
720
GG~TGTTTGGTGGTGCT~TGTAGGAAAAACTGTGCTTATTATGG~CTTATAAAC~T g l f g q a q v g k t v l l m e l l n n 2 5 3
780
GTTGCAAAAGCTCACGGTGGTTTTTCAGTGTTT~T~TGTTGGAGAGCGCACTCGTGAG v a k a h g g f s v f a g v g e r t r e 2 7 3
840
GGT~T~CCTGTACAGAGAAATGATTGAGAGT~TGTCATT~GCTA~GGAT~GCAG g n d l y r e m i e s g v i k l g d k q 2 9 3 . . . . . . . . . . . . a . . . . e . . GCT~CAGC~TGCGCCCTTGTATATGGTCAAATG~TG~CCCCCTGGTGCTCGTGCC a d s k c a l v y g q m n e p p g a r a 3 1 3 s e . . . . . . . . . . . . . . . . . . CGTGTT~TCT~CTGGGC~CTGTGGCTGAGCACTTCCGTGATGCT~GGAC~GAT r v g l t g l t v a e h f r d a e g q d 3 3 3
900
96~
1020
G T ~ T T C T C T T C A T T G A C ~ T A T T T T C C G C T T C A C C C A G G C T ~ T T C A ~ G G T G T C T G C T 1080 v l l f l d n J f r f t q a n s e v s a 3 5 3 T T ~ T T ~ T C G T A T C C C A T C T G C T G T C G G T T A C C ~ C C A A C T T T G G C T A C T G A T C T G G G A ]140 l l g r i p s a v g y q p t l a t d l g 3 7 3
GGTCTCC~GAGCGTATTAC~CCACC~GAAA~TTCTATCACTTCTGTCCAGGCTATA]200 g
l
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t
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k
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1
3
9
3
TATGTGCCTGCTGATGACTTGACTGATCCTGCACCT~TAC~CCTTT~ACACTTGGAT ]260 y v p a d d l t d p a p a t t f a h l d 4 1 3 GCCAC~CTGTGTTGTCACGACAGATTTCTGAGCTG~TATCTATCCT~TGTTGATCCC 1320 a t t v l s r q i s e l g i y p a v d p 4 3 3 CTTGATTCTACATCTCGTATGCTCTCTCCTCATATTTTGGGTGAGG~CACTAC~TACT 1380 l d s t s r m l s p h i ] . q e e h y n t 4 5 3 . . . . . . . . . . . . . . . d . . . . GCTCGT~AGTGCAAAAGGTTCTTCAG~CTAC~G~TCTGC~GATATTATTGCCATTI440 a r g v q k v l q n y k n l , q d i i a i 4 7 3 TT~G~TGGATGA~TTAGTC~GATGAC~GTTGACAGTTGCCCGAGCACGG~ATCI500 i g m d e l s e d d k l t v a r a r k i , 493 . . . . . . . . . . . m . . . . . . . . CA~GG~CTTGAGCCAGCCTTTCCATGTTGCA~GTTTTCACAGGT~CCCTG~GI560 q r f l s q p f h v a e v f t g a p g k S l 3 TATGTT~GTTG~GAGAGCAT~CCAGCTTCCAG~TGTGTT~AT~AAAATATGAT 1620 y v e l k e s l t s f q g v l d g k y d 5 3 3 • . d . . . . . n . . . . . . . . . . . G A ~ T T C C A G ~ C A G T C A T T T T A C A T G G T T G G A G G C A T T G A T G A ~ T G A T A G C C ~ G G C C 1680 d l p e q s f y m v g g i d e v i a k a 5 5 3 .. s . . . . . . . . . . . . . . . ~ T ~ G A T T G C A A A G G A G T C A ~ A T C C T ~ C A G A A A C G G ~ C T C T C T C T G C A G T C T T T T 1740 d
e
k
l
a
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e
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a
. . . . . . .
References
k
GTTTGT~GGTGATTGGT~CGTTGTGGATGTGAGGTTCGATGAGGGACTGCCTCCGATT v c q v i g a v v d v r f d e g l p p i l 1 3
.
pared from leaf and laticifer showed that the c D N A encoding the fl subunit of mitochondrial ATP synthase from Hevea hybridized to a 2.1 kb transcript in both cases.
240 73
e
q . . . . . . . p , s q p s t . p . s GGTG~GG~GGTGGT~TTACT~TGAGTTCACTGGAAAGGGT~GATTG~CAG g g k g g g k l t d e f t g k g a i g q •
120 33
v
~GTAC~GA~TCCGCCGCC~CGCTGCCCCACCTC~CCTCCTCCA~G~GCCCGAG e
60 13
s
1. Boutry M, Chua N-H: A nuclear gene encoding the beta subunit of the mitochondrial ATP synthase in Nicotiana plurnbaginifolia. EMBO J 4:2159-2165 (1985). 2. Chye M-L, Kush A, Tan C-T, Chua N-H: Characterisation of c D N A and genomic clones encoding 3-hydroxy3-methylglutaryl-coenzyme A reductase from Hevea brasiliensis. Plant Mol Biol 16:567-57 (1991). 3. Downie JA, Gibson F, Cox GB: Membrane adenosine triphosphatases of prokaryotic cells. Annu Rev Biochem 48:103-131 (1979). 4. Futai M: Reconstitution of ATPase activity from the isolated ~, fl and 7 subunits of the coupling factor, F 1, of Escherichia coll. Biochem Biophys Res Comm 79: 12311237 (1977). 5. Futai M, Kanazawa H: Structure and function ofprotontranslocating adenosine triphosphatase (FoF l ): biochemical and molecular biological approaches. Microbiol Rev 47:285-312 (1983). 6. Futai M, Takato N, Maeda M: ATP synthase (H +ATPase): results by combined biochemical and molecular biological approaches. Annu Rev Biochem 58:111136 (1989). 7. Lutcke HA, Chow KC, Mickel FS, Moss KA, Kern HF, Scheele GA: Selection of A U G initiation codons differ in plants and animals. EMBO J 6:43-48 (1987). 8. von Heijne G: Mitochondrial targeting sequences may form amphiphilic helices. EMBO J 5:1335-1342 (1986). 9. Walker JE, Saraste M, Gay NJ: The unc operon. Nucleotide sequence, regulation and structure of ATP-synthase. Biochim Biophys Acta 768:164-200 (1984). 10. Westhoff P, Nelson N, Bunemann H, Herrmann RG: Localization of genes for coupling factor subunits on the spinach plastid chromosome. Curr Genet 4 : 1 0 9 - 1 2 0 (1981). 11. Yoshida M, Okamoto H, Sone N, Hirata H, Kagawa Y: Reconstitution ofthermostable ATPase capable of energy coupling from its purified subunits. Proc Natl Acad Sci U S A 74:936-940 (1977). 12. Zurawski G, Bottomley W, Whitfield PR: Structures of the genes for the fl and e subunits of spinach chloroplast ATPase indicate a dicistronic m R N A and an overlapping stop/start signal. Proc Natl Acad Sci U S A 79: 62606264 (1982).
562
a
GTTCTCTTGTCCGGAAAATTGCAG~TCAAAAAT~TCTAGGT~TGCTGGCAACAGGA
1800 TATTATTGATTTTTTTGAGGTGAAATGTGTTGGATTATG~TTCCCGTTTTAATGTGTTA 1860 T T ~ A G A G T G T G A T ~ T A T A G ~ C A G G G G A C T G C C C T G C C T G C C ~ G C C C C T C T T T T T T C 1920 TTTTTATTTATTT~T~GGGGAAAAAGAAAGGCGGG~TGTATATTTTTCCTTTTCTAT 1980 2021 TTT~T~CCT~G~CATGAAACGTGACCATTTTCACTTG(A)n
Fig. 1. Nucleotide sequence and deduced amino acid sequence of a c D N A clone encoding the beta subunit of mitochondrial ATP synthase from Hevea brasiliensis. The deduced
amino acid sequence is shown below the nucleotide sequence of its cDNA. The deduced amino acid of tobacco atp2-1 is compared with that ofHevea atp2; identical amino acids in the two atp2 polypeptides are denoted by dots, and mismatches are shown below the Hevea atp2 amino acid sequence. A potential polyadenylation site is underlined•
