DNA Sequence-/.DNA Sequencing andMapping, Vol. 3 , pp. 127-1 30 Reprints available directly from the publisher Photocopying permitted by license only
0 1992 Harwood Academic Publishers GmbH Printed in the United Kingdom
SHORT COMMUNICATION
The sea urchin erg homolog defines a highly conserved erg-specific domain Mitochondrial DNA Downloaded from informahealthcare.com by University of Auckland on 12/01/14 For personal use only.
SHENGMEI QI,ZHANG-QUN CHEN', TAKlS S. PAPAS and JAMES A. LAUTENBERGER Laboratory of Molecular Oncology, National Cancer Institute, Frederick, M D 2 1702- 120 1, USA
GenBank M81067
A genomic clone, isolated from a phage library prepared from the DNA of the sea urchin Lytechinus variegatus, was shown by sequence analysis to be a homolog of the ets family genes, ERG and Hi-I. It contains an open reading frame of which the coding region begins at a consensus 3' splice site and extends for 173 amino acid residues. The first 84 amino acids are homologous with all members of the ets gene family, while the remainder of the sequence is only homologous with the human ERG and murine Hi-l genes. This latter region, designated R, represents a highly conserved erg-specific domain. KEY WORDS: Echinodermata
proto-oncogene,
evolution,
3'
splice
genes. Four products of ets family genes have been shown to bind DNA; these are the human and murine efs-1, murine PU.l, and Drosophila 74E proteins (Karim et a/., 1990). The murine GABPa protein can bind D N A when complexed with another subunit (Thompson et a/., 1991). An approximately 85 amino acid segment of the C region that i s common to these sequences has been postulated to be the domain responsible for sequence-specific DNA binding (Karim et a/., 1990). The human ERG gene was isolated as two distinct cDNA species that hybridized to an ets probe ( R a o et al., 1987; Reddy et a/., 1987). Due to alternate splicing, the ERG7 mRNA codes for a 363 amino acid protein, and the ERG2 mRNA codes for a 462 amino acid protein. In addition to the C region, the ERG gene shares some homology with ets-1 and ets-2 genes in an amino-terminal region designated A (Watson et a/., 1988). While the human ERG gene i s on the same chromosome as the human ETSZ gene (chromosome 21; Rao ef a/., 1988), it has a different expression pattern. The murine gene, F/i-1, described by Ben-David et a / . (1991) is closely related to the human ERG gene. However, this gene i s not the true murine ERG homolog, since its human homolog, ERGB/FL/7, has been mapped to chromosome 1 1 (Baud et a/., 1991;Watson eta/., i n press). We have investigated the ets gene family in the sea urchin as this animal has been widely studied by developmental biologists. The sea urchin belongs to the phylum Echinodermata, which together with the' chordates are members of the deuterostomes. The deuterostomes differ in their pattern of early development from the other major
site,
The ets family of genes represents cellular sequences with homology to the avian leukemia virus E26, a virus that specifices a polyprotein that also contains gag and myb sequences (Nunn et a / . , 1983; Leprince et a/., 1983).The ets sequences are responsible for the erythroblastosis caused by viral infection (Nunn and Hunter, 1989). All vertebrates examined have two distinct ets genes designated ets-1 and efs-2. The sequences (see Lautenberger ef a/., 1992, for review) have been determined for the ets-1 and ets-2 genes from the human, mouse, chicken, and Xenopus. The sea urchin and fruit fly also contain ets genes. Each of these closely related ets genes share a homologous region of about 1 10 amino acid residues called the C region. Genes less closely related to the prototype E26 v-ets gene include the human ERG and ELK genes, the mouse PU.l/Spi-1, Fli-7 and GABPa genes and the Drosophila elg and ecdysone-induced puff 74E
'Current address: Department of Pathology, Queen's University, Kingston, Ontario, Canada K7L 3N6.
127
128
S. QI ET AL.
Mitochondrial DNA Downloaded from informahealthcare.com by University of Auckland on 12/01/14 For personal use only.
group of coelomate animals, the proterostomes, that include arthropods such as Drosophila. The echinoderms thus represent an useful bridge between vertebrates ,ind Drosophila for the study of the evolutionary history of conserved genes. We report here that in addition to an ets gene, the sea urchin contains an erg homolog. The nucleotide sequence of the ets-related segment of phage 18FA (Chen et a/., 1988) from the
sea urchin Lytechinus variegatus revealed a consensus 3 ' splice site near the 5 ' end of a signiticant open reading frame (Figure I A ) . The segment extending from the first codon 3 ' of the splice site to the termination codon codes for 173 arnino acids. The first 84 of these amino acids share honiology with a subset of the C region (C') that is common to all members of the ets family. Their sequence is most similar to the human ERG and
A 1
GCGCACTGTITACCAAAGGTGGTAGCTAGTACACATTAACG
91
ATCCAACTGTGGCAGmCTTCTGGAGCTTCTATCCGACAGTTCCAACGCTAACTGCATCACATGGGAGGGTACCAACGGTGAGTTCAAG I Q L W Q F L L E L L S D S S N A N C I T W E G T N G E F K
180
ATGACCGATCCTGATGAAGTAGCCAGAAGATGGGGAGAAAGAAAAAGCAAACCTAACATGAACTACGACAAGCTAAGTCGAGCCCTGCGC
270
181
M 271
E
V
A
R
R
W
G
E
R
K
S
K
P
N
M
N
Y
D
K
L
S
R
A
L
R
Y
Y
D
K
N
I
M
T
K
V
H
G
K
R
Y
A
Y
K
F
D
F
A
G
L
A
Q
A
M
Q
V
Q
A
D
P
S
M
Y
R
Y
Q
S
D
L
T
Y
L
P
G
Y
H
P
T
K
L
N
F
V
P
I
N
P
S
T
N
A
S
L
F
S
S
H
S
S
Y
W
S
S
P
T
G
A
N
I
Y
P
450
G
540
S
GGTCACGTGACACATCCTCACGCAAGTCACATGTCCTCACACATAGGCACTTACTACGGATAACACCAAGTGTCC~GCCCG~GTAAA 630 G
631
D
ACACCAATCAACCCGTCCACCAATGCCAGCCTCTTCAGCTCTCACAGTTCATACTGGTCATCTCCCACGGGTGCAAATATCTACCCCAGT
T 541
P
CCAGTTCAGGCCGATCCTAGCATGTACCGATATCAGTCCGACCTCACCTACCTACCTGGATACCACCCGACCAAAC~AAC~GTGGGT P
451
D
TACTACTATGACAAGAACATCATGACCAAGGTACATGGAAAGCGATACGCGTATAAG~CGAC~CGCTGGACTAGCTCAAGCCATGCAA 360 Y
361
T
CGrrrCTTCATTAlTITGTTTCTGCAG
H
V
ACCCGG
T
H
P
H
A
S
H
M
S
S
H
I
G
T
Y
Y
G
'
636
B
____)
Suerg HuERG Mo F I l . 7
S G Q I Q L W Q F L L E L L S D S S N A N C I T W E G T N G E F K M T D P D E V ARRWGERKSK __________ ---------S S--------_ _ _ _ _ _ _ _ _ _ -------A-- S---------
Su erg
ALRYYYDKNI
C'
__________ __________ __________ __________
- - - --
Suerg HU ERG
LNFVG T P I M - - -APHP-A V---PSHPSS
~
I
--------- --
-----
FAGLAQ AMQPVQADPS MYRYQSDLTY -L--HPPES- - H - I - L-K-P---P- - H - I - - -L--HPTET- --K-P--IS-
60
_ _ _ _ _ _ _ - - 350 _
_ _ _ _ _337 _ _ _ _ .
c'TR
MTKVHGKRYA YKF
------ --------- ----
Hu ERG Mo F / /7
PNMNYDKLSR
LPGY HPTK MGS-HA--QM-S-HA-QQ-
118 410 397
Rf--
MoFlII
NPSTNASLFS SHSSYWSSPT GANIYPSGHV THPHASHMSS H I G T Y Y G -RLPT---P- L - - - L - V - S S - F - A APNP- - N - -G. - - -N M-V-SS-F-G AA-Q--T--AG - - - N P S PRHPNT-VP- - L - S - -
-
173 462 452
Figure 1 rhc. wca urchin crg related segment (A) Nucleotide sequence The box and arrow denote the consensus 3 ' splice siIe thdt conlorins to t h r rule5 ot Mount (1982) (B) Comparison of the sea urchin erg, human E R G and mouse FIi 1 deduced ,imincJ ,~citl wqucnt ('s l h i . m i ur( hin erg arnino acid sequence is compared with the human ERG sequence (Rao et , I / 1987)
0 1992 Harwood Academic Publishers GmbH Printed in the United Kingdom
SHORT COMMUNICATION
The sea urchin erg homolog defines a highly conserved erg-specific domain Mitochondrial DNA Downloaded from informahealthcare.com by University of Auckland on 12/01/14 For personal use only.
SHENGMEI QI,ZHANG-QUN CHEN', TAKlS S. PAPAS and JAMES A. LAUTENBERGER Laboratory of Molecular Oncology, National Cancer Institute, Frederick, M D 2 1702- 120 1, USA
GenBank M81067
A genomic clone, isolated from a phage library prepared from the DNA of the sea urchin Lytechinus variegatus, was shown by sequence analysis to be a homolog of the ets family genes, ERG and Hi-I. It contains an open reading frame of which the coding region begins at a consensus 3' splice site and extends for 173 amino acid residues. The first 84 amino acids are homologous with all members of the ets gene family, while the remainder of the sequence is only homologous with the human ERG and murine Hi-l genes. This latter region, designated R, represents a highly conserved erg-specific domain. KEY WORDS: Echinodermata
proto-oncogene,
evolution,
3'
splice
genes. Four products of ets family genes have been shown to bind DNA; these are the human and murine efs-1, murine PU.l, and Drosophila 74E proteins (Karim et a/., 1990). The murine GABPa protein can bind D N A when complexed with another subunit (Thompson et a/., 1991). An approximately 85 amino acid segment of the C region that i s common to these sequences has been postulated to be the domain responsible for sequence-specific DNA binding (Karim et a/., 1990). The human ERG gene was isolated as two distinct cDNA species that hybridized to an ets probe ( R a o et al., 1987; Reddy et a/., 1987). Due to alternate splicing, the ERG7 mRNA codes for a 363 amino acid protein, and the ERG2 mRNA codes for a 462 amino acid protein. In addition to the C region, the ERG gene shares some homology with ets-1 and ets-2 genes in an amino-terminal region designated A (Watson et a/., 1988). While the human ERG gene i s on the same chromosome as the human ETSZ gene (chromosome 21; Rao ef a/., 1988), it has a different expression pattern. The murine gene, F/i-1, described by Ben-David et a / . (1991) is closely related to the human ERG gene. However, this gene i s not the true murine ERG homolog, since its human homolog, ERGB/FL/7, has been mapped to chromosome 1 1 (Baud et a/., 1991;Watson eta/., i n press). We have investigated the ets gene family in the sea urchin as this animal has been widely studied by developmental biologists. The sea urchin belongs to the phylum Echinodermata, which together with the' chordates are members of the deuterostomes. The deuterostomes differ in their pattern of early development from the other major
site,
The ets family of genes represents cellular sequences with homology to the avian leukemia virus E26, a virus that specifices a polyprotein that also contains gag and myb sequences (Nunn et a / . , 1983; Leprince et a/., 1983).The ets sequences are responsible for the erythroblastosis caused by viral infection (Nunn and Hunter, 1989). All vertebrates examined have two distinct ets genes designated ets-1 and efs-2. The sequences (see Lautenberger ef a/., 1992, for review) have been determined for the ets-1 and ets-2 genes from the human, mouse, chicken, and Xenopus. The sea urchin and fruit fly also contain ets genes. Each of these closely related ets genes share a homologous region of about 1 10 amino acid residues called the C region. Genes less closely related to the prototype E26 v-ets gene include the human ERG and ELK genes, the mouse PU.l/Spi-1, Fli-7 and GABPa genes and the Drosophila elg and ecdysone-induced puff 74E
'Current address: Department of Pathology, Queen's University, Kingston, Ontario, Canada K7L 3N6.
127
128
S. QI ET AL.
Mitochondrial DNA Downloaded from informahealthcare.com by University of Auckland on 12/01/14 For personal use only.
group of coelomate animals, the proterostomes, that include arthropods such as Drosophila. The echinoderms thus represent an useful bridge between vertebrates ,ind Drosophila for the study of the evolutionary history of conserved genes. We report here that in addition to an ets gene, the sea urchin contains an erg homolog. The nucleotide sequence of the ets-related segment of phage 18FA (Chen et a/., 1988) from the
sea urchin Lytechinus variegatus revealed a consensus 3 ' splice site near the 5 ' end of a signiticant open reading frame (Figure I A ) . The segment extending from the first codon 3 ' of the splice site to the termination codon codes for 173 arnino acids. The first 84 of these amino acids share honiology with a subset of the C region (C') that is common to all members of the ets family. Their sequence is most similar to the human ERG and
A 1
GCGCACTGTITACCAAAGGTGGTAGCTAGTACACATTAACG
91
ATCCAACTGTGGCAGmCTTCTGGAGCTTCTATCCGACAGTTCCAACGCTAACTGCATCACATGGGAGGGTACCAACGGTGAGTTCAAG I Q L W Q F L L E L L S D S S N A N C I T W E G T N G E F K
180
ATGACCGATCCTGATGAAGTAGCCAGAAGATGGGGAGAAAGAAAAAGCAAACCTAACATGAACTACGACAAGCTAAGTCGAGCCCTGCGC
270
181
M 271
E
V
A
R
R
W
G
E
R
K
S
K
P
N
M
N
Y
D
K
L
S
R
A
L
R
Y
Y
D
K
N
I
M
T
K
V
H
G
K
R
Y
A
Y
K
F
D
F
A
G
L
A
Q
A
M
Q
V
Q
A
D
P
S
M
Y
R
Y
Q
S
D
L
T
Y
L
P
G
Y
H
P
T
K
L
N
F
V
P
I
N
P
S
T
N
A
S
L
F
S
S
H
S
S
Y
W
S
S
P
T
G
A
N
I
Y
P
450
G
540
S
GGTCACGTGACACATCCTCACGCAAGTCACATGTCCTCACACATAGGCACTTACTACGGATAACACCAAGTGTCC~GCCCG~GTAAA 630 G
631
D
ACACCAATCAACCCGTCCACCAATGCCAGCCTCTTCAGCTCTCACAGTTCATACTGGTCATCTCCCACGGGTGCAAATATCTACCCCAGT
T 541
P
CCAGTTCAGGCCGATCCTAGCATGTACCGATATCAGTCCGACCTCACCTACCTACCTGGATACCACCCGACCAAAC~AAC~GTGGGT P
451
D
TACTACTATGACAAGAACATCATGACCAAGGTACATGGAAAGCGATACGCGTATAAG~CGAC~CGCTGGACTAGCTCAAGCCATGCAA 360 Y
361
T
CGrrrCTTCATTAlTITGTTTCTGCAG
H
V
ACCCGG
T
H
P
H
A
S
H
M
S
S
H
I
G
T
Y
Y
G
'
636
B
____)
Suerg HuERG Mo F I l . 7
S G Q I Q L W Q F L L E L L S D S S N A N C I T W E G T N G E F K M T D P D E V ARRWGERKSK __________ ---------S S--------_ _ _ _ _ _ _ _ _ _ -------A-- S---------
Su erg
ALRYYYDKNI
C'
__________ __________ __________ __________
- - - --
Suerg HU ERG
LNFVG T P I M - - -APHP-A V---PSHPSS
~
I
--------- --
-----
FAGLAQ AMQPVQADPS MYRYQSDLTY -L--HPPES- - H - I - L-K-P---P- - H - I - - -L--HPTET- --K-P--IS-
60
_ _ _ _ _ _ _ - - 350 _
_ _ _ _ _337 _ _ _ _ .
c'TR
MTKVHGKRYA YKF
------ --------- ----
Hu ERG Mo F / /7
PNMNYDKLSR
LPGY HPTK MGS-HA--QM-S-HA-QQ-
118 410 397
Rf--
MoFlII
NPSTNASLFS SHSSYWSSPT GANIYPSGHV THPHASHMSS H I G T Y Y G -RLPT---P- L - - - L - V - S S - F - A APNP- - N - -G. - - -N M-V-SS-F-G AA-Q--T--AG - - - N P S PRHPNT-VP- - L - S - -
-
173 462 452
Figure 1 rhc. wca urchin crg related segment (A) Nucleotide sequence The box and arrow denote the consensus 3 ' splice siIe thdt conlorins to t h r rule5 ot Mount (1982) (B) Comparison of the sea urchin erg, human E R G and mouse FIi 1 deduced ,imincJ ,~citl wqucnt ('s l h i . m i ur( hin erg arnino acid sequence is compared with the human ERG sequence (Rao et , I / 1987)
