Sequence conservation patterns
in the DEDD family. This abbreviated sequence alignment was generated
by ClustalX with some editing based on BLAST searches. The focus
is on the DEDD RNases, but some DEDD DNases are also listed for
comparison. Sequences are from the NCBI non-redundant protein sequence
database, unless otherwise stated. Emphasis has been placed on presenting
a wide variety of sequences, rather than on completeness due to
space limitations. Included are the eight E.coli DEDD
family members: EX1_ECOLI, DNA exonuclease I (accession
no. G462029); EXOX_ECOLI, DNA exonuclease X (G9789746);
DP3E_ECOLI, DNA polymerase III ɛ subunit
(G118805); RNT_ECOLI, RNase T (G266952); ORN_ECOLI,
oligoribonuclease (G1730261); RND_ECOLI, RNase D (G133152);
DPO1_ECOLI, DNA polymerase I (G118825); DPO2_ECOLI,
DNA polymerase II (G118829); six S.cerevisiae DEDD RNases:
ORN_YEAST, yeast oligoribonuclease (G1730818); REX1_YEAST,
yeast RNA exonuclease 1 (G2131716); REX3_YEAST, yeast RNA
exonuclease 3 (G6323136); REX4_YEAST, yeast RNA exonuclease
4 (G6324493); PAN2_YEAST, Pan2p subunit of yeast poly(A)-binding
protein-dependent poly(A) nuclease (G1709565); RRP6_YEAST,
yeast exosome component Rrp6p (G6324574); and proteins from other
model organisms: EX1_HAEIN, H.influenzae DNA exonuclease
I (G1169569); DP3E_AQUAE, Aquifex aeolicus DNA
polymerase III ɛ subunit (G6014995);
DPO3_BACSU, B.subtilis DNA polymerase
III α chain (G118793); DP3E_HAEIN, H.influenzae DNA polymerase III ɛ subunit
(G1169396); RNT_VIBCH, Vibrio cholerae RNase
T (G9655469); RNT_BUCSP, Buchnera sp. RNase
T (G10038870); RNT_XYLFA, Xylella fastidiosa RNase
T (G9107281); RNT_PSEAE, Pseudomonas aeruginosa RNase
T (G9949677); RNT_HAEIN, H.influenzae RNase
T (G1173107); ORN_HAEIN, H.influenzae oligoribonuclease
(G1176352); ORN_MYCTU, Mycobacterium tuberculosis oligoribonuclease
(G7227904); ORN_HUMAN, human oligoribonuclease (G7227908);
YAA4_SCHPO, S.pombe Pan2p homolog (G1175466);
YPO4_CAEEL, C.elegans Pan2p homolog (G1730942);
PAN2_DROME, Drosophila melanogaster Pan2p
homolog (G7303975); PAN2_HUMAN, human Pan2p homolog (translated from
AC023500 with confirmation from ESTs, missing the very C-terminus
in G7662258); PARN_HUMAN, human DAN nuclease, a poly(A)-specific
3′ to 5′ exoribonuclease
(G4505611); PARN_SCHPO, S.pombe DAN nuclease
homolog (G7491557); PARN_CAEEL, C.elegans DAN
nuclease homolog (G7505706); RND_HAEIN, H.influenzae RNase
D (G1173094); RND_RICPR, Rickettsia prowazekii RNase
D (G7467941); RND_MYCTU, M.tuberculosis Rv2681
protein, a RNase D homolog (G7477317); PMC2_HUMAN, human
polymyositis-scleroderma overlap syndrome-related nucleolar 100
kDa protein (PM/Scl autoantigen P100) (G8928564); PMC2_DROME, D.melanogaster homolog of PM/Scl autoantigen
P100 (G7299933); DPOL_ARCFU, Archaeoglobus
fulgidus DNA polymerase (G3122019); DPOD_HUMAN, human
DNA polymerase δ catalytic chain (G118839);
DPOE_HUMAN, human DNA polymerase ɛ catalytic
subunit A (G1352309); EGL_DROME, D.melanogaster
egl gene product (G7291631); WRN_HUMAN, human Werner
syndrome helicase (G6136393); RND_SYNY3, Synechocystis hypothetical
protein (G1001530); RP422_RICPR, R.prowazekii hypothetical
protein RP422 (G7467752). The three conserved DEDD motifs are indicated
at the top. Highly conserved residues among all family members are
highlighted in red. The star at the top marks the fifth highly-conserved
acidic residue (highlighted in red) between motifs II and III. Number
of residues from the N-termini or residues between conserved blocks
are indicated in parentheses. Residues that are highly conserved
only within a subfamily are highlighted in blue. Yellow squares
highlight some of the characteristic sequence motifs of subfamilies
such as two of the three positively-charged, aromatic motifs specific
to RNase T proteins, the sequence motif around the fifth conserved
acidic residue in oligoribonucleases, and the characteristic motif
III of RNase D.