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Riboswitches: the oldest regulatory system?
Mikhail Gelfand
December 2004
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Riboflavin biosynthesis pathway
ribAribA
ribA ribB
G TP cyclohydrolase II
ribD
ribD
ribG
ribG
P yrim id ine deam inase
3,4-D HB P synthase P yrim id ine reductase
ribHribH R ibo flavin synthase, -cha in
ribEribB
ypaA
R ibo flavin synthase, -chain
GTP
2,5-diam ino-6-hydroxy-4-(5`-phosphoribosylamino)pyrim idine
ribulose-5-phosphate
PENTOSE-PHOSPHATE PATHWAY
PU RINE BIO SYNTHESIS PATHWAY
3,4-dihydroxy-2-butanone-4-phosphate 5-am ino-6-(5`-phosphoribitylam ino)uracil
5-am ino-6-(5`-phosphoribosylamino)uracil
6,7-dimethyl-8-ribityllumazine
Riboflavin
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5’ UTR regions of riboflavin genes from various bacteria 1 2 2’ 3 Add. 3’ Variable 4 4’ 5 5’ 1’ =========> ==> <== ===> -><- <=== -> <- ====> <==== ==> <== <========= BS TTGTATCTTCGGGG-CAGGGTGGAAATCCCGACCGGCGGT 21 AGCCCGTGAC-- 8 4 8 -----TGGATTCAGTTTAA-GCTGAAGCCGACAGTGAA-AGTCTGGAT-GGGAGAAGGATGAT BQ AGCATCCTTCGGGG-TCGGGTGAAATTCCCAACCGGCGGT 19 AGTCCGTGAC-- 8 5 8 -----TGGATCTAGTGAAACTCTAGGGCCGACAGT-AT-AGTCTGGAT-GGGAGAAGGATATG BE TGCATCCTTCGGGG-CAGGGTGAAATTCCCGACCGGCGGT 20 AGCCCGCGA--- 3 4 3 -----AGGATCCGGTGCGATTCCGGAGCCGACAGT-AT-AGTCTGGAT-GGGAGAAGGATGCC HD TTTATCCTTCGGGG-CTGGGTGGAAATCCCGACCGGCGGT 19 AGTCCGTGAC-- 10 4 10 ----–TGGACCTGGTGAAAATCCGGGACCGACAGTGAA-AGTCTGGAT-GGGAGAAGGAAACG Bam TGTATCCTTCGGGG-CTGGGTGAAAATCCCGACCGGCGGT 23 AGCCCGTGAC-- 8 4 8 ----–TGGATTCAGTGAAAAGCTGAAGCCGACAGTGAA-AGTCTGGAT-GGGAGAAGGATGAG CA GATGTTCTTCAGGG-ATGGGTGAAATTCCCAATCGGCGGT 2 AGCCCGCAA--- 3 4 3 ------AGATCCGGTTAAACTCCGGGGCCGACAGTTAA-AGTCTGGAT-GAAAGAAGAAATAG DF CTTAATCTTCGGGG-TAGGGTGAAATTCCCAATCGGCGGT 2 AGCCCGCG---- 7 6 7 --------ATTTGGTTAAATTCCAAAGCCGACAGT-AA-AGTCTGGAT-GGAAGAAGATATTT SA TAATTCTTTCGGGG-CAGGGTGAAATTCCCAACCGGCAGT 6 AGCCTGCGAC-- 11 3 11 ----–CTGATCTAGTGAGATTCTAGAGCCGACAGTTAA-AGTCTGGAT-GGGAGAAAGAATGT LLX ATAAATCTTCAGGG-CAGGGTGTAATTCCCTACCGGCGGT 2 AGCCCGCGA--- 4 4 4 -----ATGATTCGGTGAAACTCCGAGGCCGACAGT-AT-AGTCTGGAT-GAAAGAAGATAATA PN AACTATCTTCAGGG-CAGGGTGAAATTCCCTACCGGTGGT 2 AGCCCACGA--- 3 4 3 -----ATGATTTGGTGAAATTCCAAAGCCGACAGT-AT-AGTCTGGAT-GAAAGAAGATAAAA TM AAACGCTCTCGGGG-CAGGGTGGAATTCCCGACCGGCGGT 3 AGCCCGCGAG-- 5 4 5 ----–TTGACCCGGTGGAATTCCGGGGCCGACGGTGAA-AGTCCGGAT-GGGAGAGAGCGTGA DR GACCTCTTTCGGGG-CGGGGCGAAATTCCCCACCGGCGGT 15 AGCCCGCGAA-- 8 12 9 ----–CCGATGCCGCGCAACTCGGCAGCCGACGGTCAC-AGTCCGGAC-GAAAGAAGGAGGAG TQ CACCTCCTTCGGGG-CGGGGTGGAAGTCCCCACCGGCGGT 3 AGCCCGCGAA-- 5 4 5 -----CCGACCCGGTGGAATTCCGGGGCCGACGGTGAA-AGTCCGGAT-GGGAGAAGGAGGGC AO AATAATCTTCAGGG-CAGGGTGAAATTCCCGATCGGCGGT 2 AGTCCGCGA--- 7 7 7 -----AGGAACCGGTGAGATTCCGGTACCGACAGT-AT-AGTCTGGAT-GGAAGAAGATGAAA DU TTTAATCTTCAGGG-CAGGGTGAAATTCCCGATCGGTGGT 2 AGTCCGCGA--- 13 4 12 -----AGGAACTAGTGAAATTCTAGTACCGACAGT-AT-AGTCTGGAT-GGAAGAAGAGCAGA CAU GAAGACCTTCGGGG-CAAGGTGAAATTCCTGATCGGCGGT 20 AGCCCGCGA--- 3 4 3 -----AGGACCCGGTGTGATTCCGGGGCCGACGGT-AT-AGTCCGGAT-GGGAGAAGGTCGGC FN TAAAGTCTTCAGGG-CAGGGTGAAATTCCCGACCGGTGGT 2 AGTCCACG---- 5 4 5 -------GATTTGGTGAAATTCCAAAACCGACAGT-AG-AGTCTGGAT-GGGAGAAGAATTAG TFU ACGCGTGCTCCGGG-GTCGGTGAAAGTCCGAACCGGCGGT 3 AGTCCGCGAC-- 8 5 8 -----TGGAACCGGTGAAACTCCGGTACCGACGGTGAA-AGTCCGGAT-GGGAGGTAGTACGTG SX -AGCGCACTCCGGG-GTCGGTGAAAGTCCGAACCGGCGGT 3 AGTCCGCGAC-- 8 5 8 -----TTGACCAGGTGAAATTCCTGGACCGACGGTTAA-AGTCCGGAT-GGGAGGCAGTGCGCG BU GTGCGTCTTCAGGG-CGGGGTGAAATTCCCCACCGGCGGT 30 AGCCCGCGAGCG 137 GTCAGCAGATCTGGTGAGAAGCCAGAGCCGACGGTTAG-AGTCCGGAT-GGAAGAAGATGTGC BPS GTGCGTCTTCAGGG-CGGGGCGAAATTCCCCACCGGCGGT 21 AGCCCGCGAGCG 8 4 8 GTCAGCAGATCTGGTCCGATGCCAGAGCCGACGGTCAT-AGTCCGGAT-GAAAGAAGATGTGC REU TTACGTCTTCAGGG-CGGGGTGCAATTCCCCACCGGCGGT 31 AGCCCGCGAGCG 7 5 7 GTCAGCAGATCTGGTGAGAGGCCAGGGCCGACGGTTAA-AGTCCGGAT-GAAAGAAGATGGGC RSO GTACGTCTTCAGGG-CGGGGTGGAATTCCCCACCGGCGGT 21 AGCCCGCGAGCG 11 3 11 GTCAGCAGATCCGGTGAGATGCCGGGGCCGACGGTCAG-AGTCCGGAT-GGAAGAAGATGTGC EC GCTTATTCTCAGGG-CGGGGCGAAATTCCCCACCGGCGGT 17 AGCCCGCGAGCG 8 4 8 GACAGCAGATCCGGTGTAATTCCGGGGCCGACGGTTAG-AGTCCGGAT-GGGAGAGAGTAACG TY GCTTATTCTCAGGG-CGGGGCGAAATTCCCCACCGGCGGT 67 AGCCCGCGAGCG 8 3 8 GTCAGCAGATCCGGTGTAATTCCGGGGCCGACGGTTAA-AGTCCGGAT-GGGAGAGGGTAACG KP GCTTATTCTCAGGG-CGGGGCGAAATTCCCCACCGGCGGT 20 AGCCCGCGAGCG 8 4 8 GTCAGCAGATCCGGTGTAATTCCGGGGCCGACGGTTAA-AGTCCGGAT-GGGAGAGAGTAACG HI TCGCATTCTCAGGG-CAGGGTGAAATTCCCTACCGGTGGT 2 AGCCCACGAGCG 26 9 30 GTCAGCAGATTTGGTGAAATTCCAAAGCCGACAGT-AA-AGTCTGGAT-GAAAGAGAATAAAA VK GCGCATTCTCAGGG-CAGGGTGAAATTCCCTACCGGTGGT 14 AGCCCACGAGCG 11 9 11 GTCAGCAGATTTGGTGAGAATCCAAAGCCGACAGT-AT-AGTCTGGAT-GAAAGAGAATAAGC VC CAATATTCTCAGGG-CGGGGCGAAATTCCCCACCGGTGGT 13 AGCCCACGAGCG 5 4 5 GTCAGCAGATCTGGTGAGAAGCCAGGGCCGACGGTTAC-AGTCCGGAT-GAGAGAGAATGACA YP GCTTATTCTCAGGG-CGGGGTGAAAGTCCCCACCGGCGGT 40 AGCCCGCGAGCG 16 6 16 GTCAGCAGACCCGGTGTAATTCCGGGGCCGACGGTTAT-AGTCCGGAT-GGGAGAGAGTAACG AB GCGCATTCTCAGGG-CAGGGTGAAAGTCCCTACCGGTGGT 25 AGCCCACGAGCG 16 4 27 GTCAGCAGATTTGGTGCGAATCCAAAGCCGACAGTGAC-AGTCTGGAT-GAAAGAGAATAAAA BP GTACGTCTTCAGGG-CGGGGTGCAATTCCCCACCGGCGGT 18 AGCCCGCGAGCG 10 4 10 GTCAGCAGACCTGGTGAGATGCCAGGGCCGACGGTCAT-AGTCCGGAT-GAGAGAAGATGTGC AC ACATCGCTTCAGGG-CGGGGCGTAATTCCCCACCGGCGGT 16 AGCCCGCGAGCA 10 3 11 ---CGCAGATCTGGTGTAAATCCAGAGCCGACGGT-AT-AGTCCGGAT-GAAAGAAGACGACG Spu AACAATTCTCAGGG-CGGGGTGAAACTCCCCACCGGCGGT 34 AGCCCGCGAGCG 6 6 6 GTCAGCAGATCTGGTG 52 TCCAGAGCCGACGGT 31 AGTCCGGAT-GGAAGAGAATGTAA PP GTCGGTCTTCAGGG-CGGGGTGTAAGTCCCCACCGGCGGT 13 AGCCCGCGAGCG 7 3 7 GTCAGCAGATCTGGTGCAACTCCAGAGCCGACGGTCAT-AGTCCGGAT-GAAAGAAGGCGTCA AU GGTTGTTCTCAGGG-CGGGGTGCAATTCCCCACCGGCGGT 17 AGCCCGCGAGCG 7 9 7 GTCAGCAGATCCGGTGAGAGGCCGGAGCCGACGGT-AT-AGTCCGGAT-GGAAGAGGACAAGG PU AAACGTTCTCAGGG-CGGGGTGCAATTCCCCACCGGCGGT 19 AGCCCGCGAGCG 19 4 18 GTCAGCAGACCCGGTGTGATTCCGGGGCCGACGGTCAC-AGTCCGGATGAAGAGAGAACGGGA PY TAACGTTCTCAGGG-CGGGGTGCAACTCCCCACCGGCGGT 19 AGCCCGCGAGCG 15 4 16 GTCAGCAGACCCGGTGTGATTCCGGGGCCGACGGTCAT-AGTCCGGATGAAGAGAGAGCGGGA PA TAACGTTCTCAGGG-CGGGGTGAAAGTCCCCACCGGCGGT 19 AGCCCGCGAGCG 14 4 13 GTCAGCAGACCCGGTGCGATTCCGGGGCCGACGGTCAT-AGTCCGGATAAAGAGAGAACGGGA MLO TAAAGTTCTCAGGG-CGGGGTGAAAGTCCCCACCGGCGGT 16 AGCCCGCGAGCG 8 5 8 GTCAGCAGATCCGGTGTGATTCCGGAGCCGACGGTTAG-AGTCCGGAT-GAAAGAGGACGAAA SM AAGCGTTCTCAGGG-CGGGGTGAAATTCCCCACCGGCGGT 34 AGCCCGCGAGCG 8 3 8 GTCAGCAGATCCGGTCGAATTCCGGAGCCGACGGTTAT-AGTCCGGAT-GGAAGAGAGCAAGC BME GCTTGTTCTCGGGG-CGGGGTGAAACTCCCCACCGGCGGT 17 AGCCCGCGAGCG 10 15 10 GTCAGCAGATCCGGTGAGATGCCGGAGCCGACGGTTAA-AGTCCGGAT-GGAAGAGAGCGAAT BS ATCAATCTTCGGGG-CAGGGTGAAATTCCCTACCGGCGGT 18 AGCCCGCGA--- 5 4 5 -----AGGATTCGGTGAGATTCCGGAGCCGACAGT-AC-AGTCTGGAT-GGGAGAAGATGGAG BQ GTCTATCTTCGGGG-CAGGGTGAAAATCCCGACCGGCGGT 27 AGCCCGCGA—-- 3 5 3 -----AGGATTTGGTGTGATTCCAAAGCCGACAGT-AT-AGTCTGGAT-GGGAGAAGATGGAG BE ATTCATCTTCGGGG-CAGGGTGAAATTCCCGACCGGCGGT 20 AGCCCGCGA--- 3 4 3 -----AGGATCCGGTGCGAGTCCGGAGCCGACAGT-AT-AGTCTGGAT-GGGAGAAGATGAAG CA AATGATCTTCAGGG-CAGGGTGAAATTCCCTACCGGCGGT 2 AGCCCGCGAG-- 3 4 3 ----TATGATCCGGTTTGATTCCGGAGCCGACAGT-AA-AGTCTGGAT-GAAAGAAGATATAT DF GAAGATCTTCGGGG-CAGGGTGAAATTCCCTACCGGCGGT 2 AGCCCGCG---- 6 4 6 -------GATTTGGTGAGATTCCAAAGCCGACAGT-AA-AGTCTGGAT-GAGAGAAGATATTT EF GTTCGTCTTCAGGGGCAGGGTGTAATTCCCGACCGGTGGT 3 AGTCCACGAC-- 5 3 5 ----ATTGAATTGGTGTAATTCCAATACCGACAGT-AT-AGTCTGGAT—-AAAGAAGATAGGG LLX AAATATCTTCAGGG-CACCGTGTAATTCGGGACCGGCGGT 21 ACTCCGCGAT-- 4 4 4 ----–TTGAAGCAGTGAGAATCTGCTAGCGACAGT-AA-AGTCTGGAT-GGAAGAAGATGAAC LO GTTCATCTTCGGGG-CAGGGTGCAATTCCCGACCGGTGGT 3 AGTCCACGAT-- 3 10 3 ----TTGACTCTGGTGTAATTCCAGGACCGACAGT-AT-AGTCTGGAT-GGGAGAAGATGTTG PN AAGAGTCTTCAGGG-CAGGGTGAAATTCCCGACCGGCGGT 125 AGTCCGTG---- 3 4 3 -------GATGTGGTGAGATTCCACAACCGACAGT-AT-AGTCTGGAT-GGGAGAAGACGAAA ST AAGTGTCTTCAGGG-CAGGGTGTGATTCCCGACCGGCGGT 14 AGTCCGCG---- 3 4 3 -------GATGTGGTGTAACTCCACAACCGACAGT-AT-AGTCTGGAT-GAGAGAAGACCGGG MN AAGTGTCTTCAGGG-CAGGGTGAGATTCCCGACCGGCGGT 104 AGTCCGCG---- 3 4 3 -------GATGTGGTGAAATTCCACAACCGACAGT-AA-AGTCTGGAT-GGGAGAAGACTGAG SA ATTCATCTTCGGGG-TCGGGTGTAATTCCCAACCGGCAGT 6 AGCCTGCGAC-- 11 3 11 ----–CTGATCTAGTGAGATTCTAGAGCCGACAGT-AT-AGTCTGGAT-GGGAGAAGATGGAG AMI TCACAGTTTCAGGG-CGGGGTGCAATTCCCCACTGGCGGT 14 AGCCCGCGC--- 5 5 5 ------TGATCTGGTGCAAATCCAGAGCCAACGGT-AT-AGTCCGGAT-GGAAGAAACGGAGC DHA ACGAACCTTCGAGG-TAGGGTGAAATTCCCGACCGGCGGT 20 AGCCCGCAAC-- 11 4 11 --CGACTGACTTGGTGAGACTCCAAGGCCGACGGT-AT-AGTCCGGAT-GGGAGAAGGTACAA FN AATAATCTTCGGGG-CAGGGTGAAATTCCCGACCGGTGGT 2 AGTCCACG---- 4 6 4 -------GATTTGGTGAAATTCCAAAACCGACAGT-AG-AGTCTGGAT-GAGAGAAGAAAAGA GLU ---TGTTCTCAGGG-CGGGGCGAAATTCCCCACCGGCGGT 28 AGCCCGCGAGCG 10 4 10 GTCAGCAGATCCGGTTAAATTCCGGAGCCGACGGTCAT-AGTCCGGAT-GCAAGAGAACC---
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Conserved secondary structure of the RFN-element
NNNNyYYUC
NNNNrRRAG
NgGGNcCC
rgGGxc
ARRgxuAG
GRCCYG
AcCG
AGCCRGY
GG YRCC
GRYBy CYRVrG N
YGNaA N U U x N
Nx
AGU
UrN A g
Y
variab lestem -loop
additionalstem -loop
3 4
2
1
5
5 ’ 3 ’
u K NRA
xK
*
****
Capitals: invariant (absolutely conserved) positions.
Lower case letters: strongly conserved positions.
Dashes and stars: obligatory and facultative base pairs
Degenerate positions: R = A or G; Y = C or U; K = G or U; B= not A; V = not U. N: any nucleotide. X: any nucleotide or deletion
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Attenuation of transcription
TerminatorThe RFN element
Antiterminator
Antiterminator
Bam GACAAAAAAATATTGATTGTATCCTTCGGGGCTGGGTG --- TCTGGATGGGAGAAGGATGA 59 ----------GTAAAGCCCCGAATGTGTAA---ACATTCGGGGCTTTTTGACGCCAAAT BS GGACAAATGAATAAAGATTGTATCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGGATGA 59 ----------CTAAAGCCCCGAATTTTTTA--TAAATTCGGGGCTTTTTTGACGGTAAA BQ CTATAATTTGAGCAAACAGCATCCTTCGGGGTCGGGTG --- TCTGGATGGGAGAAGGATAT 250 -----------CCAAACCCCAAGGATATTAAA--ATCCTTGGGGTTTTTTGTTTTTTTT BE ACATAACGATATAGTGATGCATCCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGGATGC 155 ------------TGAGCCCCCGGGGACAT--------CCCGGGGGTTTCATTTTTATTG HD AAATTGAATAATTAATTTTTATCCTTCGGGGCTGGGTG --- TCTGGATGGGAGAAGGAAAC 148 -------------ATGCCCCGTGAGAACAAAA-----TCTCTGGGGCTTTTTTGCGCGC CA TAATGGTAATTTAATAGGATGTTCTTCAGGGATGGGTG --- TCTGGATGAAAGAAGAAATA 34 -------------AATCTCCGAAGGATTACC----TTTCTTTGGAGATTTTTTTATTTG DF TAAATATAAATTTAATACTTAATCTTCGGGGTAGGGTG --- TCTGGATGGAAGAAGATATT 63 ------------TAAACCCTGAGTTAATT--------CTCAGGGTTTTTTGTTTAAAAA LLX ACTTTAGCTACAATTGAATAAATCTTCAGGGCAGGGTG --- TCTGGATGAAAGAAGATAAT 127 ----------AAAAGACCCTGAAATTTT------ATTTTAGGGTCTTATTTTTTATTAG PN* ATCATCTGTAATTGAATAACTATCTTCAGGGCAGGGTG --- TCTGGATGAAAGAAGATAAA 81 ----------TGTATGCCTTGAGTAGTCCCC---TATTCAAGGTATATTTTTTTGGAGG PN* ATCATCTGTAATTGAATAACTATCTTCAGGGCAGGGTG --- TCTGGATGAAAGAAGATAAA 19 ------------CGTGCTCTGAAATGATTACTTGTCATTTCAGAGCATTTTTGTTAATC TM AAAACTGAATACAAAAGAAACGCTCTCGGGGCAGGGTG --- TCCGGATGGGAGAGAGCGTG 13 -----------ATGGGACCCGAGA----------------GGGTCCCTTTTCTTTTACA AO ATTTGCAACAATTTTTTAATAATCTTCAGGGCAGGGTG --- TCTGGATGGAAGAAGATGAA 33 --------TTTACAAGCCTTGAGATCGAAAG----ATTTCAAGGCTTTTTTCATCATTA DU AATTTTTTTAATACTATTTTAATCTTCAGGGCAGGGTG --- TCTGGATGGAAGAAGAAGAG 47 --------TGCATAAGCCTTGAGATCTTAG----GATTTCAAGGCTTTTTCATTAGTTA FN TAATCGAATATGTAAAATAAAGTCTTCAGGGCAGGGTG --- TCTGGATGGGAGAAGAATTA 18 ----------ATATTGCTCAGACTTT------------GTTTGAGCATTTTTTTATTAA SA TATAACAATTTCATATATAATTCTTTCGGGGCAGGGTG --- TCTGGATGGGAGAAAGAATG 74 ------TTTTCTCCTTGCATCTTAATT----------GATGTGAGGATTTTTGTTTATA DHA ACTCTTTTTAGATGAATACGAACCTTCGAGGTAGGGTG --- TCCGGATGGGAGAAGGTACA 43 -----------GTTTATGCCTCGAGGAACACCATTTCCTCGAGGCATTTTTGTTCTTTC FN GAAAAATAAATATTAAAAATAATCTTCGGGGCAGGGTG --- TCTGGATGAGAGAAGAAAAG 40 ------------CTTACCCGAATTCTAT------------AATTCGGTTTTTTTATTTT CA AATATAAAAAAATAAAGAATGATCTTCAGGGCAGGGTG --- TCTGGATGAAAGAAGATATA 19 ----------–-TATGCCCTGACGTTTTT---------CGTTGGGGCTTTTTTAATGCT DF AAAATTAAAAAATCAAAGAAGATCTTCGGGGCAGGGTG --- TCTGGATGAGAGAAGATATT 45 ----------ATAAAAACTCGAAGATAGGG----TCTTCGAGTTTTTTGTTTTTCCTAA BS TAATTAAATTTCATATGATCAATCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGATGGA 103 --AAAGAACCTTTCCGTTTTCGAGTAAGATGTGATCGAAAAGGAGAGAATGAAGTGAAA BQ GGGAAAATAGAATATCGGTCTATCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGATGGA 54 -------ATTCTCCCTTTGTGTAAA------------ACACAAAGGGTTTTTTCGTTCTATG BE ATAAAAATGTATAAGCGATTCATCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGATGAA 114 --------GGCAGCCTTCTTCTTGTGAGGATGAATCACGAGAAGGGGAGGAGAACAAGCATG PN GTTTTTTGTTATGATAAAAGAGTCTTCAGGGCAGGGTG --- TCTGGATGGGAGAAGACGAA 137 -–AACTTCTTCTGATTTTATAG------------AAAATTGGAGGAACCTGTTATGACA ST TAAATCTGCTATGCTAGAAGTGTCTTCAGGGCAGGGTG --- TCTGGATGAGAGAAGACCGG 130 ---GGAACTTCTTTCAATTTGAAA-----------AAATTGGAGGAATTTTTTAATGTC MN ATTTTTTGATATGCTATAAGTGTCTTCAGGGCAGGGTG --- TCTGGATGGGAGAAGACTGA 138 ---–GGCCTTCTTTCGATTTGTAA-----------AAATTGGAGGAATTTTTTTATGAA SA AAATTTAATAATGTAAAATTCATCTTCGGGGTCGGGTG --- TCTGGATGGGAGAAGATGGA 17 --------TCCTCCTATTCTTACG--------AGATGAATGGAAGGAGAAAATTGAATATG EF AAAAAATATAATACAAGGTTCGTCTTCAGGGGCAGGGT --- GTCTGGATAAAGAAGATAGG 33 ---CTACTCTATTTTTCCCTGCAGA------------AAAATAGGGTTTTTTTGTATGA LLX TTTTTGTGCTATAATAAAAATATCTTCAGGGCACCGTG --- TCTGGATGGAAGAAGATGAA 66 -–TCAACTTCCTCGAAATTTGAAGAAT-TATTTTCTCATATTTGGAGGTTTTTTTATGT LO ATTGTAAGAAAATATTCGTTCATCTTCGGGGCAGGGTG --- TCTGGATGGGAGAAGATGTTG 79 ---ATGCACAAACTCTCCCTCAACTTTTTTTA--------GTTGAGGTTTTTTATTTGC
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Attenuation of translation
EC AATCCGCTTATTCTCAGGGCGGGGCG --- TCCGGATGGGAGAGAGTAACG 59 ----------CTGCCCTGATTCTGGTAACCATAATTTTAGTGAGGTTTTT-------TACCATGAATCAGACGCTA TY AACCCGCTTATTCTCAGGGCGGGGCG --- TCCGGATGGGAGAGGGTAACG 61 ----------CTGCCCTGATTCTGGTAACCATAATGTTAATGAGGTTTTTT------TACCATGAATCAGACGCTA KP ATCTCGCTTATTCTCAGGGCGGGGCG --- TCCGGATGGGAGAGAGTAACG 61 ----------CTGCCCTGATTCTGGTAACCATAATTTTAATGAGGTTTTTT------TACCATGAATCAGACGCTC HI TTAGCTCGCATTCTCAGGGCAGGGTG --- TCTGGATGAAAGAGAATAAAA 41 ----------CAGCCCTGATTCTGGTATTTAATTGAAATCTCAAAT-TAGGAAAT--TACTATGAATCAGTCAATT VK TATTTGCGCATTCTCAGGGCAGGGTG --- TCTGGATGAAAGAGAATAAGC 76 ----------CAGCCCTGATTCTGGTATCTAAATATCTTTATATTTCAAGGAATT--TACTATGAATCAGTCTATT AB TAGGCGCGCATTCTCAGGGCAGGGTG --- TCTGGATGAAAGAGAATAAAA 54 ----------CCGCCCTGATTCTGGTATAAATTCATCTTATTAAA—AAGGCATT---TACTATGAATCAGTCATTA YP ATGGGGCTTATTCTCAGGGCGGGGTG --- TCCGGATGGGAGAGAGTAACG 194 ----------CCGCCCTGATTCTGGTAATCCATAATTTTTTAATGAGGTTTCT---TTACCATGAATCAGACGCTT VC CACAACAATATTCTCAGGGCGGGGCG --- TCCGGATGAGAGAGAATGACA 83 ----------AAGCCCTGATTCTGGTCATTTTTT--------------GGAGTATT--ACCATGAATCAGTCCTCA Spu CTATCAACAATTCTCAGGGCGGGGTG --- TCCGGATGGAAGAGAATGTAA 145 ----------ACGCCCTGATTCTGGATATTCCCATGTCGTATTTTTGAAGGATATTAA-CCATGAATCAGTCTTTA MLO GACGTTAAAGTTCTCAGGGCGGGGTG --- TCCGGATGAAAGAGGACGAAA 44 -------CGTGCGTCCTGATTCTGGTTCGAAACGGA--------------AGGATGGACCCATGAATCAGCATTCC AC AAGCGACATCGCTTCAGGGCGGGGCG --- TCCGGATGAAAGAAGACGACG 51 ----------CAGTCCTGAAATGTTTAACCGTAATT-------------------TACGAGAGCATTTCATATGTC BP AAGCAGTACGTCTTCAGGGCGGGGTG --- TCCGGATGAGAGAAGATGTGC 62 ----------TAGCCCTGAAACGTTTTTCGCCATTTCCTTTTTT------------GCGAGAGCGTTTCAATGTCC BPS AGTCAGTGCGTCTTCAGGGCGGGGCG --- TCCGGATGAAAGAAGATGTGC 86 ----------GAGCCCTGAAACGTTTTTCGCCCATTCATGTTTC-----------GCGAGGAGCGTTTCACATCATG BU AATCAGTGCGTCTTCAGGGCGGGGTG --- GCCGGATGGAAGAAGATGTGC 99 ----------ATGCCCTGAAACGTTTTTCGCCCAACTTTT--------------GCGATGAGCGTTTCAACTATGT REU CATCGTTACGTCTTCAGGGCGGGGTG --- TCCGGATGAAAGAAGATGGGC 77 ----------ATCCCCTGAAACGCCCATCCATGGAAATCCACGCAC-------------GGAGCGTTTCAATGCTG RSO GCTTGGTACGTCTTCAGGGCGGGGTG --- TCCGGATGGAAGAAGATGTGC 80 ---------CGTGCCCTGGAACGTCTTGTCGCCCATTTCA---------------GCGAGGAGCGTTTCCATGTTG PP GGTCGGTCGGTCTTCAGGGCGGGGTG --- TCCGGATGAAAGAAGGCGTCA 50 ----------TCGCCCCGAGACGTTCATCGATCATTCA------------------CGAGGAGCGTTTCATGTTCA PY GCCGGTAACGTTCTCAGGGCGGGGTG --- CCGGATGAAGAGAGAGCGGGA 91 ----------ATGCCCTGTTTTTTCATTAAATT---------------------AAACAGGAGTCAGAACACGTGC PU CGGCGAAACGTTCTCAGGGCGGGGTG --- CCGGATGAAGAGAGAACGGGA 68 ----------ACGCCCTGTTTTTCACAC--------------------------AAACAGGAGTCAGAACATGCAA PA GGCCGTAACGTTCTCAGGGCGGGGTG --- CCGGATAAAGAGAGAACGGG 53 ---------AAAGCCCTGTTTTTCAC---------------------------GAAACAGGAGTTCGTCATATG-- BME CGCGGGCTTGTTCTCGGGGCGGGGTG --- TCCGGATGGAAGAGAGCGAAT 54 ----------GCGCCCTGATTCTAGTTTCGTG--------------------------AGGAACCTATGAACCAAA CAU AATCCGAAGACCTTCGGGGCAAGGTG --- TCCGGATGGGAGAAGGTCGGC 116 ------CGCGATGCCCCGAAGGTGTG-----------------------------TTCAGGGGTGTCGCGATGAAC TFU GTACACACGCGTGCTCCGGGGTCGGT --- GGATGGGAGGTAGTACGTGGT 58 -------GCCTTACCCCGGAGCCTGACCT-------------------------GGCTAGGGGGAAGGCTTCTCGCATG GLU TGAGTTTTGTTCTCAGGGCGGGGCG --- TCCGGATGCAAGAGAACCG 32 ---------AAGGCCCCGAGGATTACATGCTTTTAAATCCTTTGAAAAGGGGACAAGATCATGAATCCTATAACCG DR GAACCGACCTCTTTCGGGGCGGGGCG --- TCCGGACGAAAGAAGGAGGAG 1 GACGCTCAGCTTGCCCCCCA------------------------------------GCAGGCGGCGTCCGCGTATG SM GTCGCAAGCGTTCTCAGGGCGGGGTG --- TCCGGATGGAAGAGAGCAAGC 45 ATCATTGGAAAAATGCCAACCCTGAAA-------------------GGCTTGAGACCATGACCATACTT TQ TTCGGCACCTCCTTCGGGGCGGGGTG --- TCCGGATGGGAGAAGGAGGGCCACTTGCGC AMI CTTACTCACAGTTTCAGGGCGGGGTG --- TCCGGATGGAAGAAACGGAGCGCCTTATGG
SD-sequestorThe RFN element
Antisequestor
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RFN: the mechanism of regulation
• Transcription attenuation
• Translation attenuation
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Distribution of RFN-elements
Genomes Number of analyzed genomes
Number of genomes with RFN
Number of the RFN elements
α-proteobacteria 8 4 4
β-proteobacteria 7 4 4
γ-proteobacteria 17 15 15
δ- and ε-proteobacteria 3 0 0
Bacillus/Clostridium 12 12 19
Actinomycetes 9 4 4
Cyanobacteria 5 0 0
Other eubacteria 7 5 6
Total 68 47 52
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Phylogenetic tree of RFN-elements
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YpaA: riboflavin transporter in Gram-positive bacteria
• 5 predicted transmembrane segments => a transporter• Upstream RFN element (likely co-regulation with riboflavin
genes) => transport of riboflaving or a precursor• S. pyogenes, E. faecalis, Listeria sp.: ypaA, no riboflavin
pathway => transport of riboflavinPrediction: YpaA is riboflavin transporter (Gelfand et al., 1999)
Verification:• YpaA transports flavines (riboflavin, FMN, FAD) (by genetic
analysis, Kreneva et al., 2000)• ypaA is regulated by riboflavin (by microarray expression
study, Lee et al., 2001)• … via attenuation of transcription (and to some extent
inhibition of translaition) (Winkler et al., 2003)
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More predicted (riboflavin) transporters
impX from Fusobacterium and Desulfitobacterium
– no similarity with any known protein; no homologs in other complete genomes
– 9 predicted TMS
– single RFN-regulated gene
pnuX from Actinomycetes (Corynebacterium, Streptomyces, Thermomonospora)
– no orthologs in other genomes
– 6 predicted TMS
– either a single gene or a part of the riboflavin operon
– regulated by RFN
– similar to the nicotinamide mononucleotide transporter PnuC from E. coli
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thi-box and regulation of thiamine metabolism genes by pyrophosphate (Miranda-Rios et al., 2001)
TTCGGGATCCGCGGAACCTGA-TCAGGCTAA-TACCTGCG-AAGGGAACAAGAGTTA THIC_EC TTCGGGATCCGTTGAACCTGA-TCAGGTTAA-TACCTGCG-AAGGGAACAAGAGAAG THIC_VC GCAGTGACCCGTTGAACCTGA-TCCAGTTCA-TACTGGCG-TAGGGACGGTGCAAGC THIC_MLO GCAGTGACCCGTTGAACCTGA-TCCAGTTCA-CACTGGCG-TAGGGACGGTGCAGAC THIC_SM AGAAATACCCTTTACACCCGA-TCGGGATAA-TACCTGCG-TGGGGAGTTTTCACGG THIC_NM TTCTTAACCCTTTGGACCTGA-TCTGGTTCG-TACCAGCG-TGGGGAAGTAGAGGAA thiC_BS CCGTCGACCGTACGAACCTGA--CCGGGTAA-TGCCGGCG-TAGGGAGTTGCAAATG THIC_MT GGATCGACCCTTTGAACCTGA-TCCGGGTAA-TGCCGGCG-GAGGGAAATTATGTCG THIT2_TVO TCCTCGACCCCAAGAACCTGA-TCCGGGTAA-TGCCGGCG-GAGGGATCGGGGAAGG thi1_TM
Notation: Red– Conserved nucleotides; Green– Purine or Pyrimidine conserved nucleotides; Blue– Non-conserved nucleotides
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Alignment of THI-elements 1 2 3 3' FACULTATIVE STEM-LOOP 2' 4 5 5' 4' 1' ----====>===> -=====> <===== ========> <======= <=== ===> =====> <===== <=== <====---- BACILLUS/CLOSTRIDIUM GROUP BS_THIC TAGTTACTGGGGGTGCCCGCT----------------TTCcgGGCTGAGAGAGAAGGCA-------------AGCTTCTTAACCCTTT---GGACCTGA-TCTGGTTCG-TACCAGCG-TGGGGA-AGTAGAGGA BS_TENA TAACCACTAGGGGTGTCCTTC----------------ATAAGGGCTGAGATAAAAGTGT-------------GACTTTTAGACCCTCA---TAACTTGA-ACAGGTTCA-GACCTGCG-TAGGGA-AGTGGAGCG BS_YLMB TTCATCCTAGGGGTGCTTTG-------------------CGAAGCTGAGAGAGACTT-----------------TGTCTCAACCCTTT---TGACCTGA-TCTGGATCA-TGCCAGCG-GAGGGA-AGCGGTGAA BS_YKOF AAAGCACTAGGGGTGCTGT--------------------TTTGGCTGAGATAAAGCGCGGAA-----GAAACGCGCTTTGATCCCTTA---TGACCCGA-TCTGGATAA-TACCAGCG-TGGGGA-AGTGCAGGT SA_TENA GAACTACTAGGGGAGCCTAAT----------------GATATGGCTGAGATGAATT-------------------GTTCAGACCCTTA---TGACCTGA-TTTGGTTAG-TACCAACG-TAGGAA-AGTAGTTAT SA_YKOE CACACACTAGGGGTGTTT----------------------TATACTGAGATGAGGCTT---------------GCCCTCAAACCCTTT---GAACCTGA-TCTAGCTTG-AACTAGCG-TAGGAA-AGTGTTACT LLX_YUAJ TTTGCACAATGGGTCTATTGACAAA---------ACTGTCAGTAGCGAGA----------------------------AATACCATC----TGACCTGA-TCTGGGTAA-TGCCAGCG-TAGGAA-TGTGTTAAG CA_THIS ATAGTTAACGGGGAGCCTGTA-----------------GACAGGCTGAGAGTGGAATG--------------TGATTCCAGACCCTCA---TAACCTGA-TTTGGATAA-TGCCAACG-TAGGGA-GTTAATGCA CA_YUAJ TATGTGCTAGGGGTGCCTT---------------------TAGGCTGAGAAACAGTTT--------------GTCACGTTAACCCTT-----AACCTGA-TCTGGATAA-TACCAGCG-TAGGGA-AGCAGTTTG ST_YUAJ TTTCACAAAGGAGTGCTT-----------------------TGGCTGAGATCGCAA------------------TTGCGAAATCCTGA---GGACCTGA-TCTTGTTAG-TACAAGCG-TAGGGA-TTGTGACCA DHA_THIC TAATCACTAGGGGGGCCGAATA---------------AGGTCGGCTGAGATAAAGGACCCA---------AGAATCCTTTGACCCTT-----AACCTGA-TCTGGGTAA-TGCCAGCG-TAGGGAAGGTGGATAA LMO_TENA GAAAAACTAGGGGGGCCGAT-------------------TCTGGCTGAGATAGGAAGGTAAT-----------GCTTTCTGACCCTTT---GAACCTGT-TT--GTTAG-TGCAAGCG-TAGGGA-AGTGAATGT LMO_YUAJ TTACCACAGGGGGGGCTTC---------------------TTAGCTGAGATTGAGTCCACGTGT-----TTTTGGATTCTGACCCTTT---GAACCTGT-TC--GTTAA-TACGAGCG-TAGGGA-TTGTGGCGA PROTEOBACTERIA EC_THIB GTTCTCAACGGGGTGCCACGCGT------------ACGCGTGCGCTGAGAAA---------------------------ATACCCGTCGA---ACCTGA-TCCGGATAA-CGCCGGCG-AAGGGATTTGAGGC EC_THIM AAACGACTCGGGGTGCCCTTCTGC-------------GTGAAGGCTGAGAAA----------------------------TACCCGTATC---ACCTGA-TCTGGATAA-TGCCAGCG-TAGGGA-AGTCACG EC_THIC TTTCTTGTCGGAGTGCCTTA-------------------ACTGGCTGAGACCGTTT------------------ATTCGGGATCCGCGGA---ACCTGA-TCAGGCTAA-TACCTGCG-AAGGGA-ACAAGAG VC_THIC CCACTTGTCGGAGTGCCAT---------------------TGGGCTGAGACCGTTT------------------ATTCGGGATCCGTTGA---ACCTGA-TCAGGTTAA-TACCTGCG-AAGGGA-ACAAGAG VC_THID CCTGTAGTCGGGGAGCCTGAGAG-- 66 5 71 -AATTAAAGGCTGAGATCGCGT-------------------AGCGAGACCCGTTGA---ACCTGA-TTCAGTTAG-GACTGACG-TAGGGA-ACTATCC VC_THIB CCCACTCACGGGGGGCCACCCATTCAT-------CCGAATGGCGCTGAGATCAAGCAC---------------TGCTTGGGACCCGCA 21 -ACCTGA-ACCAGATAA-TGCTGGCG-TAGGAATTGAGCTA XFA_THIC TTTGAAGCGGGGGTACCATAGCCA------------AGCTGCGGTTGAGAC----------------------------ACACCCTTCGA---ACCTGA-TCCGGTTTA-CACCGGCG-TAGGAAAGCTTCGT MLO_THIC CATTCACCAGGGGAGTCCCGG----------------CAAGGGGCTGAGATACTGCTGGCTTTC------GCGGCGCAGTGACCCGTTGA---ACCTGA-TCCAGTTCA-TACTGGCG-TAGGGACGGTGCAA MLO_THIB CGCTCTAACGGGGTGCCGGA------ 5 3 5 -----GACCGGCTGAGAGGCAGT------------------CTCGCCAACCCGCTGA---ACCTGA-TCCGGTTTG-TACCGGCG-GAGGGA-TTAGACG MLO_YK GCCCATCCACAGGGGTGCTCCGTAC-------------GGTCGGGGCTGAGACGGGGGCGG-----------CAAGCCCACAGACCCTAGA----AGCTGA-TCTGGGTAA-TACCAGCG-GAGCGA-GGCGGGCG NX_CITX CTCCTTGTCGGAGTGCCGCCGC---------------CGGGCGGCTGAGATTGCGA------------------AAGCAGAATCCGTAGA---ACCTGT--CGGGGTAA-TGCCTGCG-TAGGAA-ACAAACC NX_THIC ATTGAAACAGGGGTGCTGCCTGAT----------GTTTAGGCGGCTGAGAA----------------------------ATACCCTTTAC---ACCCGA-TCGGGATAA-TACCTGCG-TGGGGA-GTTTTCA ACTINOBACTERIAE MT_THIO CTGTAGACACGGGAGTCCCGGG--------------AGCGGGGTCTGAGAGTGGGCGCGCCT-------------GCCCTTACCGTCAC----ACCTGA-TCCGGATCA-TGCCGGCG-AAGGGAGGTCAAGGATG MT_THIC GTACCCACGCGGGAGCGCACGC--------------CGAGTGCGCTGAGAGGACGGCTCGGG------------GCCGTCGACCGTACGA---ACCTGA--CCGGGTAA-TGCCGGCG-TAGGGAGTTGCAAATG CGL_THIC CAGTCCCCACGGGCGCCCGA-----------------GCACGGGCTGAGATCGCGCTGATT---------GCTGCGCGAGCACCGTTTGA---ACCTG--TCCGGTTAG-CACCGGCG-AAGGAAGAGAGGAATGGTGCAATG CGL_THID ACTAGGCACGGGGTGCCAACCGGATGG---AAAAATTCCGGAGGCTGAGAAA---------------------------ACACCCGTTGA---ACCTGC-TCTAGCTCG-TACTAGCG-AAGGGATGGCCTTAACGTG CGL_THIE CTTACCCCACGGGTGCCCAAT---------------GCATTGGGCTGAGATTGCGCGCTGT---------TGCTGCGCGGGACCGTTCGA---ACCTG--TCTGGTTAA-CACCAGCG-AAGGAAGCGAGGATTGATTGTCCCGTG CGL_YKOE TCATAGACACGGGTGCTCGGTGA------------AAATCCGGGCTGAGATCTGGCA----------------TAGCCACGACCGTCGA----ACCTG-ATCCGGATAA-TGCCGGCG-ATAGGGAGGAAAAATATG CGL_OARX TAGTGACACGGGGTGCAAAAGCACTTT----AAAAAAGCTTTCGCTGAGATT---------------------------ACACCCGTCGA---ACCTG-ATCCAGTTAG-TACTGGCG-AAGGGACTGTCGCAT CYANOBACTERIA NPU_THIC TCCATGCTAGGGGTGCCTACAT---------------AACCAGGCTGAGATC---------------------------ACACCCTTAAC---ACCTGAGTCTGGGTAA-TACCAGCG-GAGGGAAGCTGTTTATTG CY_THIC CCATAGCTAGGGGTGTCTAGAA---------------AGCTAGGCTGAGAA----------------------------AAACCCTTAGA---ACCTGAGACTGGGTAA-TACCAGCG-GAGGGAAGCTCACCATTC AN_THIC TCCATGCTAGGGGTGCTTGCAC---------------TAACAGGCTGAGATT---------------------------ACACCCTTAAC---ACCTGAGACTGGGTAA-TACCAGCG-AAGGGAAGCTGTTTATTG THERMUS/DEINOCOCCUS, THERMOTOGALES, Fusobacterium, CFB group DR_THIB CGCGTCACCGGGGGTGCCCTGCTT------------CGGCAGCGGCTGAGAAC---------------------------ACACCCCAGGA---ACCTGA-ACCGGGTCA-TTCCGGCG-GAGGGAGTGTGATGC DR_THIC ATCGTCAACAGGGGTGCCTCCGCATA--------TGGGCCGGAGGCTGAGAGGGCAACT---------------CGGGCCTAACCCTATGA---ACCTGA-ACTGGTTAG-CACCAGCG-GAGGGA-GTGTGACG TQ_THIBGGCCGTCACCGGGGGTGCCCCA------------------AAAGGGCTGAGAGC---------------------------ATACCCTTGGA---ACCTGA-TCCGGGTCA-TGCCGGCG-TAGGGAAGGTGACGGCC TM_THI1 CCTTCCCCAGGGGGAGCTCCTAT---------------TCCGGGGCTGAGAGGAGGACGG-------------AAGTCCTCGACCCCAAGA---ACCTGA-TCCGGGTAA-TGCCGGCG-GAGGGATCGGGGAAGGA FN_THIC TATATGTACTGGGGAGCTT----------------------TGTGCTGAGATTAGAACCT------------TTTTTCTTAGACCCATAGT---ACCT-GA-TTTGGATAA-TGCCAACG-AAGGGA—GTACCA FN_THIX ACTAGTTACAAGGGAGTTAATA-----------------AATTGACTGAGAAAAGGATG--------------TGAGCCTTGACCTTTTG----ACCT-GA-TTTGGATAA-TGCCAACG-TAGGAA--GTAAA PG_THIS AGACCGCTACGGGGGTGCTTGCCG--- 4 3 4 -GATACGGCAGGCTGAGAT---------------------------AATACCCATAG---ACCT-GA-TCCGGATAA-TACCGGCG-GAGGGAT-GTAG PG_OMR ATTGGGAGAAGGGGTGCTTCCTGTA--- 3 7 3 --GTGGATGGCTGAGAAC---------------------------AAACCCTCATC---ACCT-GA-ACCGGATAA-TACCGGCG-TAGGAAA-CTCTC BX_THIS TAAAGACAAAGGGGTGCCACC------------------CGGTGGCTGAGATT---------------------------ATACCCTAAGA---ACCT-GA-TGCAGTTAG-TACTGCCG-AAGGGA—TTGTG ARCHAEA TAC_T1 GGTGTGGTGGGGGAGCTCCAT-----------------AAGGGGCTGAGAGGATCCGG---------------ATGGATCGATCCCTGGA---ACCTGA-TCCGGGTAA-TACCGGCG-GAGGGAAATTATG FAC_T1 AGTTATACCGGGGAGCTAA---------------------AATGCTGAGAGGATAA-------------------GGATCGACCCGTGCA---ACCTGA-TCCGGACAA-TACCGGCG-GAGGGAGATGGATA
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Conserved secondary structure of the THI-element
MG
GG K
CC
C A
G G A
A G
C C U
THI-elem ent
Thi-box
1
4
5
2
C Y G G
G R C C
N U NR
UR
NG
YY
UC
RR
NAG
AG
A
G
3
GA U
GC
N
facultative stem -loop
Capitals: strongly conserved positions. Dashes and points: obligatory and facultative base pairs
Degenerate positions: R = A or G; Y = C or U; K = G or U; M= A or C; N = any nucleotide
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THI: the mechanism of regulation
1 ,2
1 ,2
•Thermus/Deinococcus group,•CFB group•Proteobacteria,
• Translation attenuation
•Actinobacteria,•Cyanobacteria,•Archaea
•Bacillus/Clostridium group,•Thermotoga, •Fusobacterium,•Chloroflexus
• Transcription attenuation
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Distribution of THI-elements
Genomes Number of analyzed genomes
Number of genomes
with THI
Number of the THI elements
-proteobacteria 7 7 15
-proteobacteria 6 6 12
-proteobacteria 18 17 38
- and proteobacteria 3 1 1
The Bacillus/Clostridium group 18 18 51
Actinomycetes 9 9 25
Cyanobacteria 5 5 5
Other eubacteria 14 11 11
Archaea (Thermoplasma) 17 3 6
Total 97 77 164
Mandal et al., 2003: THI in 3’UTR (plants). THI in untranslated intron (fungi)
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Predicted THI-regulated genes: transporters
yuaJ: predicted thiamin transporter (possibly H+-dependent)
• Found only in the Bacillus/Clostridium group;• Occurs in genomes without the thiamin pathway (Streptococci);• Has 6 predicted transmembrane segments (TMS);• Regulated by THI-elements in all cases with only one exception (E. faecalis);• In B. cereus, the thiamin uptake is coupled to proton movement (Arch Microbiol,
1977).
thiX-thiY-thiZ and ykoF-ykoE-ykoD-ykoC: predicted ATP-dependent HMP transporters
• Found in some Proteobacteria and Firmicutes;• Not found in genomes without the thiamin pathway;• Always co-occur with thiD and thiE;• In Pasteurellae, Brucella and some Gram-positive cocci, they are present without
thiC;• Regulated by THI-elements in all cases with only one exception (T. maritima);• Putative substrate-binding protein ThiY is homologous to Thi12 from yeast, known
to be involved in the biosynthesis of HMP
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Predicted THI-regulated genes: more transporters
• thiU from P. multocida and H. influenzae belongs to the possible thiMDE-thiU operon, has 12 predicted TMS; similar to proline permease; no orthologs in other genomes
• thiV from Methylobacillus and H. volcanii clustered with thiamin genes or has THI-elements, has 13 predicted TMS , similar to the pantothenate symporter PanF from E.coli; no orthologs in other genomes
• thiW from S. pneumoniae and E. faecalis forms an operon with thiamin genes, has 5 predicted TMS; no homologs in other complete genomes
• pnuT from the CFB group of bacteria forms operon with thiamin-related genes; has 6 TMS; similar to the nicotinamide mononucleotide transporter PnuC from E.coli; no orthologs in other genomes
• cytX from Neiserria and Chloroflexus has 12 TMS, similar to the cytosine permease CodB from E. coli, forms an operon with thiamin genes in Neiserria and Pyrococcus; homologs in other genomes are not regulated by THI-elements.
• thiT1 and thiT2 from three different Thermoplasma (Archaea) are two paralogous genes; have 9 TMS; belong to the MFS family of transporters. This is the first example of THI-element-regulated genes in Archaea
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The PnuC family of transporters
The RFN elements
The THI elements
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Predicted THI-regulated genes: enzymes
• thiN: non-orthologous displacement of thiESeparate gene in archaea or with thiD (in M. theroautotrophicum)Always present if ThiD is present and ThiE is absent
• tenA: gene of unknown function somehow associated with thiDFound in most firmicutes, some proteobacteria and archaea; ThiD-TenA gene fusions in some eukaryotes;Forms clusters with thiD and other THI-elements-regulated genes in most bacteria;Single tenA gene is also regulated by THI-elements in some bacteria;Not found in genomes without the thiamin pathway;Always co-occurs with the thiD and thiE genes
• tenI: gene of unknown function, thiE paralog Found in some unrelated bacteria;Forms a separate branch in the phylogenetic tree for thiE;In most bacteria, located in clusters of THI-elements-regulated genes.
• ylmB from Bacilli belongs to the ArgE/dapE/ACY1/CPG2/yscS family of metallopeptidases;regulated by the THI-elements in B. subtilis and B. halodurans, not regulated in B. cereus.
• thi-4 from Thermotoga maritima belongs to a family of putative thiamine biosynthetic enzymes from archaea and eukaryotes. Located in the one operon with thiC and thiD.
• oarX from Methylobacillus and Staphylococcus is a single THI-elements-regulated gene; belongs to the short-chain dehydrogenase/reductase (SDR) superfamily
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Metabolic reconstruction of the thiamin biosynthesis
= thiN (confirmed)
(Gram-positive bacteria)
(Gram-negative bacteria)
Transport of HMPTransport of HET
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THI-elements in delta-proteobacteria: co-operative binding?
• Tandem arrangement of THI-elements upstream of the main thiamine operon thiSGHFE1 in Desulfovibrio spp.
• Tandem arrangement of glycine riboswitches in B. subtilis and V. cholerae (Mandal et al., 2004):– co-operative binding of the cofactor (glycine)– rapid activation/repression– same arrangement in all glycine riboswitches
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B12-box and regulation of cobalamin metabolism genes by pyrophosphate (Nou & Kadner, 2000; Ravnum &
Andersson, 2001; Nahvi et al., 2002)
• Long mRNA leader is essential for regulation of btuB by vitamin B12.
• Involvement of highly conserved B12-box rAGYCMGgAgaCCkGCcd in regulation of the cobalamin biosynthetic genes (E. coli, S. typhimurium)
• Post-transcriptional regulation: RBS-sequestering hairpin is essential for regulation of the btuB and cbiA
• Ado-CBL is an effector molecule involved in the regulation of the cobalamin biosynthesis genes
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Conserved RNA secondary structure of the regulatory B12-element
A
A
A
AA
AA
CGd
a
aa
a
a
ktk
h
CC
c
C
C
GG
G
GGG
G
GT
M
Y
K
y
c
c G
g
g G
G
G YG
tg
g
g
gN
RN
N
NN
r
r
r
g
g C
c
c T
C
C G
CC
a
ta N
B 12 box
P 0
5' 3'
P 1
P 4 V S
B I IB I
P 5 P 6
P 2
N
A dd- I
F acultative stem- loop
A dd- I I
The group
Bacillus/Clostridium
Other taxonomic groups
-proteobacteria
base stem
CGh
G
d
yc c
C C
P 3
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A
A
A
AA
AA
CGd
a
aa
a
a
ktk
h
CC
c
C
C
GG
G
GGG
G
GT
M
Y
K
y
c
c G
g
g G
G
G YG
tg
g
g
gN
RN
N
NN
r
r
r
g
g C
c
c T
C
C G
CC
a
ta N
P 0
P 1
P 4 P 5 P 6
P 2
N
CGh
G
d
yc c
C C
P 3
B12-element
+Ado-CBL
Ado-CBL
pseudoknot
terminator
1 2 3
1 2
antiterminator
3
A
A
A
AA
AA
CGd
a
aa
a
a
ktk
h
CC
c
C
C
GG
G
GGG
G
GT
M
Y
K
y
c
c G
g
g G
G
G YG
tg
g
g
gN
RN
N
NN
r
r
r
g
g C
c
c T
C
C G
CC
a
ta N
P 0
P 1
P 4 P 5 P 6
P 2
N
CGh
G
d
yc c
C C
P 3
B12-element
+Ado-CBL
Ado-CBL
pseudoknot
RBS-sequestorhairpin
1 2
1 2
antisequestor
A. B.
The predicted mechanism of the B12-mediated regulation of cobalamin genes
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B12-element regulates cobalamin biosynthetic genes and transporters, cobalt transporters and a number of other cobalamin-related genes.
Distribution of B12-elements in bacterial genomes
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Metabolic reconstruction of
cobalamin biosynthesis: new
enzymes and transporters
Cobalt ion transportcbiMNQO, hoxN, hupE, cbtAB, cbtC, cbtD, cbtE, cbtG, cnoABCD
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If a bacterial genome contains B12-dependent and B12-independent isoenzymes, the genes encoding the B12-
independent isoenzymes are regulated by B12-elements
Ribonucleotide reductasesRibonucleotide reductases
NrdJ NrdJ ((BB1212-dependent-dependent)
NrdAB/NrdDG NrdAB/NrdDG ((BB1212-independent-independent))
+ ––
–– +
+ +
Methionine synthaseMethionine synthase
MetH MetH ((BB1212-dependent-dependent))
MetEMetE((BB1212-independent-independent))
++ ––
–– ++
++ ++
B12B12 B12
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LYS-element: lysine riboswitch
uaAG
u
CG
P 1
5' 3'base stem
R Yr y
Gy
y
r
aa
g
u g
a a a GG
r Cr G
y G Cyk
a G ug R
C a Yu
a
Gg N
a
aA
a N
acUGC
GA
G G gaR
ru
Yy
P 2
P 5P 6
P 7
P 3P 4
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Reconstruction of the lysine metabolism
-aspartyl-phosphate
aspartate semialdehyde
homoserine
dihydrodipicolinate
tetrahydrodipicolinate
N-acetyl-2-amino-6-ketopimelateN-succinyl-2-amino-6-ketopimelate
N-acetyl-L,L-diaminopimelateN-succinyl-L,L-diaminopimelate
L,L-diaminopimelate
meso -diaminopimelate
Lysine transport
L-aspartate
lysC,dapG,yclMlysC,thrA,metL
asd
hom
thrA,metL
dapA
dapB
dapDdapD
ykuR
dapC(argD)
ddh
patA
dapE
dapF, dal
lysA
predicted genes are boxed (pathway of acetylated intermediates in B. subtilis)
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Regulation of lysine catabolism: the first example of an activating riboswitch
• LYS-elements upstream of pspFkamADEatoDA operon in Thermoanaerobacter tengcongensis; kamADElysE operon in Fusobacterium nucleatum– lysine catablism pathway– LYS element overlaps candidate terminator
=> acts as activator
• similar architecture of activating adenine riboswitch upstream of purine efflux pump ydhL (pbuE) in B. subtilis (Mandal and Breaker, 2004)
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S-box (SAM riboswitch)
g u y
c a r
NaAUGc
AP 1
5' 3'base stem
u R
CA
U
U
uGa
P 4
NaGA
g
c
GR
CA
aCcD H
Gg
UGCY
a
AA NuccN
r
N
N
G gy
C cr
P 2
G GG A
C C DC
rG
N y G A a
Ac
gg
P 3
P 5g
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Reconstruction of the methionine metabolism
Cystathionine
Homocysteinemethyl-THF
Sulfide
CH
methylene-THF
THF
3
O-acetylhomoserine
Homoserine
Aspartate semialdehyde
Methionine
S-ribosyl-hom ocysteine
(SRH)
S-adenosyl-hom ocysteine
(SAH)
S-adenosyl-methionine
(SAM)
Methylthioribose (MTR)MTA
Threonine
metI yrhB
metC yrhAmetF
yxjH*
metK
mtnKSUVW XYZ
hom
cysH-...metB
metH
metX
metEmtn
mtn
metY
predicted genes are marked by *(transport, salvage cycle)
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A new family of amino acid transporters
S-box (rectangle frame)MetJ (circle frame)LYS-element (circles)Tyr-T-box (rectangles)
BC1434
FN 062 4
269.47
SON-3
CJ
CPE
LysT
MetT
TyrT
MleN
DF
CTCCB
OB
SO N-2VC-2
NM B
SON-1
VC-1
BHHP
C
TTE-nhaC
AC0744
FN0978
BL1111
CTC 00901
OB2874OB1118
NMB05 36
FN0352BC4121
EF-nhaC 1
EF-nhaC 2
PPE
LP-nha2
LP-nha1 L
L
M
G A
ELB
BS-yheL
BS-m leN
FN0650
VC2037
BC1709
SA 2292HI1107
VV21061FN207 7
BH3946
BC0373
FN14 22
BB0638
BB0637
F N1420
CTC02529SO1087
VCA0193
BT1270
C
CB
T C02520
CPE2317
FN1414
SA2117
Archaea
clostrid ia
Pasteure llaceae
malate/lactate
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Regulation of reverse pathway Met-Cys in Clostridium acetobutylicum
ubiG yrhA
antisense transcript
Cysteine
S-adenosylmethionine
yrhB
AA
Cys-T-box S-box
sense transcript
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Three methionine regulatory systems in Gram-positive bacteria: loss of S-box regulons
• S-boxes (riboswitch)– Bacillales– Clostridiales– the Zoo:
• Petrotoga
• actinobacteria (Streptomyces, Thermobifida)
• Chlorobium, Chloroflexus, Cytophaga
• Fusobacterium
• Deinococcus
• proteobacteria (Xanthomonas, Geobacter)
• Met-T-boxes (Met-tRNA-dependent attenuator)– Lactobacillales
• MET-boxes (transcription factor MtaR)– Streptococcales
Lact. Strep. Bac. Clostr.
ZOOMetJ, MetR in proteobacteria
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Riboswitches in the Sargasso sea metagenome
• 125 THI-elements
• 38 LYS-elements
• 25 B12-elements
• 9 RFN-elements
• 3 S-boxes
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Conserved structures of known riboswitches
NNNNyYYUC
NNNNrRRAG
NgGG
NcCC
Rg
GGxc G
Aux
gRRA
GRC
CYG
AcCG
AGCCRGYGG YRCC GRYBy CYRVr
G N
YGN
aA N U U x N
Nx
AGU
UrN
A gY
uK N
RA
xK
Var
Add
RFN-element
MG
GG
A
G G A
A G
C C U
THI-element
C Y G GN U N
RUR
UC
RR G
A
A
A
AA
AA
CGd
a
aa
a
a
ktk
h
CC
c
C
C
GG
G
GGG
G
GT
M
Y
K
y
c
c G
g
g G
G
G YG
tg
g
g
gN
RN
N
NN
r
r
r
g
g C
c
c T
C
C G
CC
a
ta N
B 12 box
P1
5' 3'
P2
P5 P6 P7
P3
N
base stem
CGh
G
d
yc c
C C
P4
g u y
c a r
NaAUGc
AP1
5' 3'
u R
CA
U
U
uGa
P4
NaGA
g
c
GR
CA
aCcD H
Gg
UGCY
a
AA NuccN
r
N
N
G gy
C cr
P2G GG A
C C DC
rG
N y G A a
Ac
gg
P3
P5g
AUR
UA
P1
5' 3'
C GU R
Y
CA RUAU
GG
P2
AN
U
A
C
GU N U U
A
UA
A A
G
GCC
P3
C
N G A
U
P1
P2
P3
P4
P5
P3 P2
P4
base stem base stem5' 3' 5' 3'
B12-element
base stem
S box-
base stem
G box-
Add
Add I
Add II
Add III
Var
P5
P1
uaAG
u
CG
P1
5' 3'base stem
R Yr y
Gy
y
r
aa
g
u g
aa a GG
r Cr G
y G Cyk
a G ug R
C a Yu
a
Gg N
a
aA
a N
acUGC
GA
G G gaR
r
uYy
P2
P5P6
P7
P3P4
LYS-element
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Characterized riboswitches (more are predicted)RFN Riboflavin
biosynthesis and transport
FMN (flavin mononucleo-tide)
Bacillus/Clostridium group, proteobacteria, actinobacteria, other bacteria
THI Biosynthesis and transport of thiamin and related compounds
TPP (hiamin pyrophosphate)
Bacillus/Clostridium group, proteobacteria, actinobacteria, cyanobacteria, other bacteria, archea (thermoplasmas), plants, fungi
B12 Biosynthesis of cobalamine, transport of cobalt, cobalamin-dependent enzymes
Coenzyme B12 (adenosyl-cobalamin)
Bacillus/Clostridium group, proteobacteria, actinobacteria, cyanobacteria, spirochaetes, other bacteria
S-box Metabolism of methionine and cystein
SAM (S-adenosyl- methionine)
Bacillus/Clostridium group and some other bacteria
LYS Lysine metabolism lysine Bacillus/Clostridium group, enterobacteria, other bacteria
G-box Metabolism of purines
purines Bacillus/Clostridium group and some other bacteria
glmS Synthesis of glucosamine-6-phosphate
glucosamine-6-phosphate
Bacillus/Clostridium group
gcvT Catabolism of glycine
glycine Bacillus/Clostridium group
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Mechanisms
UUUUUUUU
5 ’
33 ’
5 ’
Regulatory hairpin(terminator of transcription and or RBS-sequestor)/
In the case of regulation of transcription
In the case of regulation of translation
GENES
3 ’ GENES
RNA-element
A
5 ’
1 3UUUUUUUU
Antiterm inator/Antisequestor
3 ’ GENES
5 ’ 1 2
RNA-element
3 ’ GENES
B 5 ’
2 3
Antiterminator/Antisequestor
3 ’ GENES
C
5 ’
RNA-element
3 ’ GENES
12
5 ’
1 23 ’ GENES
Regulatory hairpin
+ Effector
UUUUUUUU
- Effector
2
1
gcvT: ribozyme, cleaves its mRNA (the Breaker group)
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Properties of riboswitches
• Direct binding of ligands• Same structure – different mechanisms• Distribution in all taxonomic groups
– diverse bacteria– archaea - thermoplasmas– eukaryotes – plants and fungi
• Lineage-specific features…• … horizontal transfer, duplications, lineage-specific loss• Correlation of the mechanism and taxonomy:
– attenuation of transcription (anti-anti-terminator) – Bacillus/Clostridium group
– attenuation of translation (anti-anti-sequestor of translation initiation) – proteobacteria
– attenuation of translation (direct sequestor of translation initiation) – actinobacteria
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• Andrei Mironov– software genome analysis, conserved RNA patterns
• Alexei Vitreschak– analysis of RNA structures
• Dmitry Rodionov– metabolic reconstruction
• Support:– Howard Hughes Medical Institute– INTAS– Russian Fund of Basic Research– Russian Academy of Sciences