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Synonyms: LexA |
Summary:
LexA represses the transcription of several genes involved in the cellular response to DNA damage or inhibition of DNA replication [11, 30] as well as its own synthesis [31] This regulation is known as the SOS response [30] which is generated by two related processes; RecF appears to facilitate RecA filament formation on the leading-strand single-stranded DNA gaps generated by replisome lesion skipping [32] When DNA is damaged, the RecA coprotease binds to the single-stranded DNA in the damaged region to form a filament [33, 34] This filament interacts with the LexA dimer to activate its self-cleavage activity by an allosteric mechanism, causing the dissociation of LexA from its DNA targets and the induction of the SOS regulon for the repair of broken DNA [35, 36] Phenylboronic compounds are able to inhibit the self-cleavage of the transcriptional repressor LexA, presumably through the formation of an acyl-enzyme intermediate [37] The conformational flexibility of unbound LexA is the key element in establishing a coordinated SOS response [38] A structurally dynamic peptide loop encoding residues 75-84 of LexA appears to be necessary for the recognition of RecA [39]. LexA is widely distributed in bacteria, and it appears that it emerged from the gram-positive group [40] It shows two domains, the N-terminal domain involved in DNA binding via a helix-turn-helix [41]and the C-terminal domain involved in dimerization and in cleavage activity [42, 43] To repress transcription, LexA blocks the access of RNA polymerase to target promoters [19] LexA dimer [44]recognizes and binds to an imperfect inverted repeat DNA sequence called the LexA box or SOS box [45, 46] Although, the majority of the LexA-regulated genes have only one SOS box, some have two or three boxes which sometimes overlap [1] The crystal structure of the LexA-DNA complex has been determined [47] The DNA-binding domains of the LexA dimer interact with the DNA in the classical fashion of a winged helix-turn-helix (HTH) motif, and they bind to the same minor groove of the DNA [47] lexA is the first gene in the lexA-dinF operon [48] dinF encodes a member of the MATE family of multidrug efflux transporters [49] The SOS system is induced by methylglyoxal (MG), based on ChIP-chip analysis with DNA-RNAP occupancy, and this involves LexA-regulated genes such as recAX, lexA-dinF, and dinB [50] High activity of LexA-regulated genes, also known as the LexA i-modulon [51], was also observed in the wild type and a Glucose Minimal Media Optimized Strain (GMOS) cultivated in the presence of hydrogen peroxide, explaining the extended lag phase observed for these strains upon peroxide treatment [52]. Read more > |
Transcription factor | ![]() ![]() |
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TF conformation(s): |
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Evolutionary Family: | LexA | ||||||||||||
Sensing class: | Using internal synthesized signals | ||||||||||||
Connectivity class: | Local Regulator | ||||||||||||
Gene name: | lexA | ||||||||||||
Genome position: | 4257115-4257723 | ||||||||||||
Length: | 609 bp / 202 aa | ||||||||||||
Operon name: | lexA-dinF | ||||||||||||
TU(s) encoding the TF: |
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Transcription factor regulation |
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Functional conformation | Function | Promoter | Sigma factor | Central Rel-Pos | Distance to first Gene | Genes | Sequence | LeftPos | RightPos | Evidence (Confirmed, Strong, Weak) | References | |
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LexA | repressor | chop | Sigma70 | -0.5 | -23.5 | cho |
ccgcctgttaCACTGGATAGATAACCAGCAttcggagtca
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1823482 | 1823501 | [AIBSCS], [APIORCISFBSCS] | [1], [2] | |
LexA | repressor | dinBp | Sigma70 | -6.5 | -24.5 | dinB, yafN, yafO, yafP |
accctgaaatCACTGTATACTTTACCAGTGttgagaggtg
|
250864 | 250883 | [AIBSCS], [APIORCISFBSCS], [ICWHO] | [1], [3] | |
LexA | repressor | dinBp2 | Sigma38 | -6.5 | -24.5 | dinB, yafN, yafO, yafP |
accctgaaatCACTGTATACTTTACCAGTGttgagaggtg
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250864 | 250883 | [AIBSCS], [APIORCISFBSCS], [ICWHO] | [1], [3] | |
LexA | repressor | dinDp | nd | 8.5 | -53.5 | dinD |
agatactcacAACTGTATATAAATACAGTTacagatttac
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3817697 | 3817716 | [GEA], [AIBSCS], [APIORCISFBSCS] | [4] | |
LexA | repressor | dinGp | Sigma70 | -27.5 | -24.5 | dinG, ybiB |
aatgccacaaTATTGGCTGTTTATACAGTAtttcaggttt
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833036 | 833055 | [GEA], [AIBSCS], [BPP] | [5], [6] | |
LexA | repressor | dinIp | Sigma70 | -7.5 | -29.5 | dinI |
aggttattttACCTGTATAAATAACCAGTAtattcaacag
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1121507 | 1121526 | [GEA], [AIBSCS], [APIORCISFBSCS], [BPP], [IHBCE], [SM] | [7], [8] | |
LexA | repressor | dinJp | Sigma70 | 89.5 | -24.5 | dinJ, yafQ |
ctacaattcaAGCTGAATAAATATACAGCAcaggagatac
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246517 | 246536 | [GEA], [AIBSCS] | [7], [9] | |
LexA | repressor | dinQp | Sigma70 | -29.5 | -223.5 | dinQ |
tgcaaggacgTGCTGGTTTTATAACCTGCAtgtactgtat
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3648002 | 3648021 | [APIORCISFBSCS] | [10] | |
LexA | repressor | dinQp | Sigma70 | -7.5 | -201.5 | dinQ |
aacctgcatgTACTGTATGATTATCCAGTTagctctgagg
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3647980 | 3647999 | [GEA], [AIBSCS], [APIORCISFBSCS] | [10], [11] | |
LexA | repressor | ftsKp1 | Sigma70 | -0.5 | -86.5 | ftsK |
ttgattacacTCCTGTTAATCCATACAGCAacagtactgg
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933128 | 933147 | [AIBSCS], [GEA], [AIBSCS], [BPP] | [5], [12] | |
LexA | repressor | ftsLp2 | nd | 3.0 | -18.0 | ftsL, ftsI, murE, murF, mraY, murD, ftsW, murG, murC, ddlB, ftsQ, ftsA, ftsZ, lpxC |
cgtagttcagTTCTGCGTATTGCAGAGAGGacgaatgcat
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91004 | 91023 | [APIORCISFBSCS] | [13], [14] | |
LexA | repressor | hokEp | Sigma24 | -81.5 | -186.5 | hokE |
aaacaggactCACTGTATAAATAAACAGCTattttgttga
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607640 | 607659 | [AIBSCS] | [1] | |
LexA | repressor | insKp | Sigma24 | nd | nd | insK | nd | nd | [GEA], [BPP] | [11] | ||
LexA | repressor | lexAp | Sigma70 | -9.0 | -37.0 | lexA, dinF |
aatcgcctttTGCTGTATATACTCACAGCAtaactgtata
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4257068 | 4257087 | [GEA], [APIORCISFBSCS], [BPP], [SM] | [15] | |
LexA | repressor | lexAp | Sigma70 | 13.0 | -16.0 | lexA, dinF |
ctcacagcatAACTGTATATACACCCAGGGggcggaatga
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4257089 | 4257108 | [GEA], [APIORCISFBSCS], [BPP], [SM] | [15] | |
LexA | repressor | phrp | nd | -66.5 | -152.5 | phr |
gccagcagctGGCTGCGCTTATCGACAGTTatcgccgtgg
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739345 | 739364 | [APIORCISFBSCS] | [7], [16] | |
LexA | repressor | phrp | nd | 25.5 | -61.5 | phr |
ttatcctgacGCCTGGCTTTCAGGGCAGCGttatttcgaa
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739436 | 739455 | [GEA], [APIORCISFBSCS] | [17] | |
LexA | repressor | polBp | Sigma70 | -40.5 | -63.5 | polB |
gggcagtaatGACTGTATAAAACCACAGCCaatcaaacga
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65834 | 65853 | [GEA], [AIBSCS], [BPP] | [5] | |
LexA | repressor | ptrAp | Sigma70 | 20.5 | -107.5 | ptrA, recB, recD |
ccagtcacggACTGATGGTTATATAAACATaggctgactc
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2958982 | 2959001 | [BPP], [SM] | [18] | |
LexA | repressor | recAp | Sigma70 | -20.0 | -70.0 | recA, recX |
aaacacttgaTACTGTATGAGCATACAGTAtaattgcttc
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2823829 | 2823848 | [BPP] | [19] | |
LexA | repressor | recNp | Sigma70 | -22.5 | -58.5 | recN |
ccagcctcttTACTGTATATAAAACCAGTTtatactgtac
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2751727 | 2751746 | [GEA], [AIBSCS], [BPP] | [20], [21] | |
LexA | repressor | recNp | Sigma70 | -0.5 | -36.5 | recN |
aaccagtttaTACTGTACACAATAACAGTAatggtttttc
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2751749 | 2751768 | [GEA], [AIBSCS], [BPP] | [20], [21] | |
LexA | repressor | recQp | Sigma70 | 6.0 | -23.0 | recQ |
aaaatagcgcCTGTTTTTATTTCAGGcaatcggggt
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4005834 | 4005849 | [GEA], [APIORCISFBSCS] | [22] | |
LexA | repressor | rpsUp3 | Sigma70 | 4.5 | -42.5 | rpsU, dnaG, rpoD |
attttgaaatAAGCTGGCGTTGATGCCAGCggcaaaccga
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3210729 | 3210748 | [BCE], [SM] | ||
LexA | repressor | ruvAp1 | nd | -63.5 | -111.5 | ruvA, ruvB |
aataaattatACTGTGCCATTTTTCAGTTCatcgagacac
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1946078 | 1946097 | [APIORCISFBSCS] | ||
LexA | repressor | ruvAp1 | nd | -12.5 | -60.5 | ruvA, ruvB |
tcttcatcctTCGCTGGATATCTATCCAGCatttttttat
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1946027 | 1946046 | [APIORCISFBSCS], [BPP] | [23] | |
LexA | repressor | ruvAp2 | nd | -72.5 | -112.5 | ruvA, ruvB |
gaataaattaTACTGTGCCATTTTTCAGTTcatcgagaca
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1946079 | 1946098 | [APIORCISFBSCS] | ||
LexA | repressor | ruvAp2 | nd | -19.5 | -59.5 | ruvA, ruvB |
cttcatccttCGCTGGATATCTATCCAGCAtttttttatc
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1946026 | 1946045 | [APIORCISFBSCS], [BPP] | [23] | |
LexA | repressor | sbmCp2 | nd | 17.5 | -24.5 | sbmC |
tttgcaactaTACTGTATATAAAAACAGTAtcaatggagg
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2081277 | 2081296 | [GEA], [IHBCE] | [24] | |
LexA | repressor | ssbp3 | Sigma70 | -46.5 | -160.5 | ssb |
acacaaattgACCTGAATGAATATACAGTAttggaatgca
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4273955 | 4273974 | [APIORCISFBSCS], [BCE] | ||
LexA | repressor | sulAp | Sigma70 | -5.0 | -33.0 | sulA |
tcactggatgTACTGTACATCCATACAGTAactcacaggg
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1020942 | 1020961 | [BCE] | ||
LexA | repressor | symEp | Sigma70 | -8.5 | -85.5 | symE |
tccccatattTACTGATGATATATACAGGTatttagcgcg
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4579916 | 4579935 | [AIBSCS], [BPP] | [11] | |
LexA | repressor | tisBp | nd | -28.0 | -244.0 | tisB |
gtccaaatatTACTGTTTATTTATACAGTAaacttctata
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3853299 | 3853318 | [GEA], [ICA] | [11] | |
LexA | repressor | umuDp | Sigma70 | -20.5 | -49.5 | umuD, umuC |
atcagtattgATCTGCTGGCAAGAACAGACtactgtatat
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1230708 | 1230727 | [APIORCISFBSCS] | [7], [25] | |
LexA | repressor | umuDp | Sigma70 | -0.5 | -29.5 | umuD, umuC |
aagaacagacTACTGTATATAAAAACAGTAtaacttcagg
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1230728 | 1230747 | [BPP] | [7], [25] | |
LexA | repressor | uvrAp | Sigma70 | -28.5 | -93.5 | uvrA |
tgcattccaaTACTGTATATTCATTCAGGTcaatttgtgt
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4273955 | 4273974 | [APIORCISFBSCS], [BCE] | ||
LexA | repressor | uvrBp1 | Sigma70 | -51.5 | -84.5 | uvrB |
tggtgatgaaCTGTTTTTTTATCCAGTataatttgtt
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813434 | 813450 | [GEA], [APIORCISFBSCS], [BPP], [ICA], [SM] | [21], [26] | |
LexA | repressor | uvrBp2 | Sigma70 | -220.5 | -284.5 | uvrB |
tattttttaaCTGGTTAGATAAATGCAatggcagtca
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813234 | 813250 | [GEA], [BPP], [ICA] | [21] | |
LexA | repressor | uvrBp2 | Sigma70 | -167.5 | -231.5 | uvrB |
tgccataaaaCTGTCATCACTCATCTTgacaaatgtt
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813287 | 813303 | [GEA], [BPP], [ICA] | [21] | |
LexA | repressor | uvrBp2 | Sigma70 | -20.5 | -84.5 | uvrB |
tggtgatgaaCTGTTTTTTTATCCAGTataatttgtt
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813434 | 813450 | [BPP], [GEA], [SM], [APIORCISFBSCS], [BPP], [ICA], [SM] | [21], [26] | |
LexA | repressor | uvrBp3 | Sigma70 | -24.5 | -398.5 | uvrB |
tccactattcCTGTGGATAACCATGTGtattagagtt
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813120 | 813136 | [GEA], [BPP], [ICA], [SM] | [21] | |
LexA | repressor | uvrCp3 | Sigma70 | nd | nd | uvrC | nd | nd | [GEA], [BPP] | [27] | ||
LexA | repressor | uvrDp1 | Sigma70 | 11.0 | -66.0 | uvrD |
taatcagcaaATCTGTATATATACCCAGCTttttggcgga
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3997907 | 3997926 | [APIORCISFBSCS] | ||
LexA | repressor | uvrYp2 | Sigma70 | -129.5 | -176.5 | uvrY, uvrC |
tcgtagggctTACTGTGAAACGATCCGGTAagccgttggt
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1995526 | 1995545 | [GEA], [AIBSCS] | [27] | |
LexA | repressor | yafNp | Sigma70 | -1.5 | -37.5 | yafN, yafO, yafP |
ttatgatgtaTACTATTATGTATATTCTGGtgtgcattat
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251958 | 251977 | [APIORCISFBSCS] | [28] | |
LexA | repressor | ybfEp | Sigma32 | -85.5 | -126.5 | ybfE |
tgattaacgcAACTGATTAAAAACCCAGCGtccgcgtcgc
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712015 | 712034 | [AIBSCS] | [1] | |
LexA | repressor | ydjMp | Sigma70 | -1.5 | -42.5 | ydjM |
cacttccgtgCACTGTATAAAAATCCTATActgtacgtat
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1810159 | 1810178 | [GEA], [AIBSCS], [BPP] | [11] | |
LexA | repressor | ydjMp | Sigma70 | 17.5 | -24.5 | ydjM |
aaaaatcctaTACTGTACGTATCGACAGTTtagtgagttt
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1810177 | 1810196 | [GEA], [AIBSCS], [BPP] | [11] | |
LexA | repressor | yebGp | Sigma70 | -9.5 | -27.5 | yebG |
aaaagaaataTACTGTATAAAATCACAGTTattatgagag
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1930765 | 1930784 | [GEA], [AIBSCS], [APIORCISFBSCS], [IHBCE] | [29] | |
LexA | repressor | yehFp | Sigma70 | 11.5 | -18.5 | yehF |
catctgcattCAACTGGATAAAATTACAGGgatgcagaat
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2196446 | 2196465 | [AIBSCS] | [11] |
Alignment and PSSM for LexA TFBSs | ![]() |
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Aligned TFBS of LexA |
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Sequence | |
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TACTGTTTTTATATACAGTATA | |
TACTGTTTATTTATACAGTAAA | |
TACTGTTTTTATATACAGTAGT | |
AACTGGTTTTATATACAGTAAA | |
AACTGTTTTTTTATCCAGTATA | |
AACTGTGATTTTATACAGTATA | |
TACTGGTTATTTATACAGGTAA | |
AACTGTATTTATATACAGTTGT | |
CCCTGGGTGTATATACAGTTAT | |
TGCTGTGAGTATATACAGCAAA | |
TGCTGGTTATCTATCCAGTGTA | |
AGCTGTTTATTTATACAGTGAG | |
TACTGTTATTGTGTACAGTATA | |
CCCTGTAATTTTATCCAGTTGA | |
CGCTGGATATCTATCCAGCATT | |
TACTGTATGATTATCCAGTTAG | |
TGCTGTATATTTATTCAGCTTG | |
AGCTGGGTATATATACAGATTT | |
TACTGTATGAGCATACAGTATA | |
TACTGTACGTATCGACAGTTTA | |
TATTGGCTGTTTATACAGTATT | |
TACTGTACATCCATACAGTAAC | |
TCCTGTTAATCCATACAGCAAC | |
TACTGTATATTCATTCAGGTCA | |
CACTGGTAAAGTATACAGTGAT | |
ACCTGTATATATCATCAGTAAA | |
CGCTGGGTTTTTAATCAGTTGC | |
GGCTGTGGTTTTATACAGTCAT | |
TGCTGGTTTTATAACCTGCATG | |
CTCTGGTTTATTGTGCAGTTTA | |
TATAGGATTTTTATACAGTGCA | |
GGCTGCGCTTATCGACAGTTAT | |
TACTGTGAAACGATCCGGTAAG | |
TACTGTGCCATTTTTCAGTTCA | |
GCCTGTTTTTATTTCAGGCAAT | |
CGCTGGCATCAACGCCAGCTTA | |
CTATGTTTATATAACCATCAGT | |
GCCTGGCTTTCAGGGCAGCGTT | |
TTGCATTTATCTAACCAGTTAA | |
GTCTGTTCTTGCCAGCAGATCA | |
CAAGATGAGTGATGACAGTTTT | |
ACACATGGTTATCCACAGGAAT | |
ACTATTATGTATATTCTGGTGT | |
TCTGCGTATTGCAGAGAGGACG |
Position weight matrix (PWM). LexA matrix-quality result |
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A 9 20 3 2 3 0 12 10 15 6 16 3 32 6 24 1 40 0 2 20 17 20 C 9 9 36 2 1 1 3 5 1 1 7 6 6 1 11 42 0 0 9 1 5 3 G 5 11 1 2 39 15 11 2 8 0 6 1 3 6 3 1 2 43 5 5 6 6 T 21 4 4 38 1 28 18 27 20 37 15 34 3 31 6 0 2 1 28 18 16 15 |
Consensus |
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; consensus.strict taCTGttttTatataCAGtaaa ; consensus.strict.rc TTTACTGTATATAAAAACAGTA ; consensus.IUPAC trCTGkktwTwtatmCAGtwww ; consensus.IUPAC.rc WWWACTGKATAWAWAMMCAGYA ; consensus.regexp t[ag]CTG[gt][gt]t[at]T[at]tat[ac]CAGt[at][at][at] ; consensus.regexp.rc [AT][AT][AT]ACTG[GT]ATA[AT]A[AT]A[AC][AC]CAG[CT]A |
Evolutionary conservation of regulatory elements | ![]() |
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