Arabidopsis thaliana (L.) Heynh. (mouse-ear cress) [ATH]

FULL NAME: DNA topoisomerase 1


DESCRIPTION:
Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 5'-OH DNA strand. The free DNA strand than undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 5'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone (By similarity).
Subcellular location: Nucleus 

MISCELLANEOUS:
Eukaryotic topoisomerase I and II can relax both negative and positive supercoils, whereas prokaryotic enzymes relax only negative supercoils.


STRUCTURE SIMILARITY:
Belongs to the eukaryotic type I topoisomerase family.


CATALYTIC ACTIVITY:
ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.


PROTEIN TYPE(S):
DNA topoisomerase


RELATED PATHWAY(S):
DNA replication


Amino acids sequence

        10         20         30         40         50         60
MGTETVSKPV MDNGSGDSDD DKPLAFKRNN TVASNSNQSK SNSQRSKAVP TTKVSPMRSP
        70         80         90        100        110        120
VTSPNGTTPS NKTSIVKSSM PSSSSKASPA KSPLRNDMPS TVKDRSQLQK DQSECKIEHE
       130        140        150        160        170        180
DSEDDRPLSS ILSGNKGPTS SRQVSSPQPE KKNNGDRPLD RASRIIKDES DDETPISSMF
       190        200        210        220        230        240
RKKIDSGMSG GNQLSNDEKK PLVQKLHQNG STVKNEVPNG KVLGKRPLEK NSSADQSSLK
       250        260        270        280        290        300
KAKISASPTS VKMKQDSVKK EIDDKGRVLV SPKMKAKQLS TREDGTDDDD DDDVPISKRF
       310        320        330        340        350        360
KSDSSNSNTS SAKPKAVKLN STSSAAKPKA RNVVSPRSRA MTKNTKKVTK DSKYSTSSKS
       370        380        390        400        410        420
SPSSGDGQKK WTTLVHNGVI FPPPYKPHGI KILYKGKPVD LTIEQEEVAT MFAVMRETDY
       430        440        450        460        470        480
YTKPQFRENF WNDWRRLLGK KHVIQKLDDC DFTPIYEWHL EEKEKKKQMS TEEKKALKEE
       490        500        510        520        530        540
KMKQEEKYMW AVVDGVKEKI GNFRVEPPGL FRGRGEHPKM GKLKKRIHPC EITLNIGKGA
       550        560        570        580        590        600
PIPECPIAGE RWKEVKHDNT VTWLAFWADP INPKEFKYVF LGAGSSLKGL SDKEKYEKAR
       610        620        630        640        650        660
NLTDHIDNIR TTYTKNFTAK DVKMRQIAVA TYLIDKLALR AGNEKDDDEA DTVGCCTLKV
       670        680        690        700        710        720
GNVECIPPNK IKFDFLGKDS IQYVNTVEVE PLVYKAIGQF QAGKSKTDDL FDELDTSKLN
       730        740        750        760        770        780
AHLKELVPGL TAKVFRTYNA SITLDEMLSQ ETKDGDVTQK IVVYQKANKE VAIICNHQRT
       790        800        810        820        830        840
VSKTHGAQIE KLTARIEELK EVLKELKTNL DRAKKGKPPL EGSDGKKIRS LEPNAWEKKI
       850        860        870        880        890        900
AQQSAKIEKM ERDMHTKEDL KTVALGTSKI NYLDPRITVA WCKRHEVPIE KIFTKSLLEK
       910
FAWAMDVEPE YRFSRR    

Encoded by TOP1ALPHA gene


OTHER NAME(S):
DNA topoisomerase 1 beta
DNA topoisomerase I alpha
MGO1
MGOUN 1
MTE17.1
MTE17_1
TOP1
TOP1ALPHA
TOP1BETA
TOPOISOMERASE 1


Nucleic acid sequence

        10         20         30         40         50         60
atgggcactg aaacagtttc aaaacctgtg atggataatg ggtctggaga cagtgatgat
        70         80         90        100        110        120
gacaagcctt tagcgttcaa gaggaataat acagtggctt ctaattcgaa tcaatctaaa
       130        140        150        160        170        180
tccaattccc agagaagcaa ggcagttcct accaccaagg tatcacctat gagatcacct
       190        200        210        220        230        240
gtgactagcc caaatggaac cactccttcg aataaaactt ctatagtgaa atcctctatg
       250        260        270        280        290        300
ccatcatctt cttctaaggc ttcaccagca aagtcaccat tgcggaatga tatgccctct
       310        320        330        340        350        360
actgttaagg ataggagcca gttacagaaa gatcagtctg aatgtaaaat tgagcatgag
       370        380        390        400        410        420
gattctgagg atgatagacc tttaagttcc atactatctg gaaataaagg gccaacctct
       430        440        450        460        470        480
tcgcggcagg tttcttcacc gcagccagag aaaaagaata atggtgatcg acctcttgat
       490        500        510        520        530        540
agagcaagca gaattataaa agacgagtca gatgatgaaa ctccaatctc gtcaatgttt
       550        560        570        580        590        600
cggaagaaga ttgatagtgg gatgtcaggg ggcaaccagc tctccaatga tgaaaagaaa
       610        620        630        640        650        660
cctttggttc aaaagttgca tcagaatggt tccacagtta agaatgaagt gccgaatggt
       670        680        690        700        710        720
aaggtattag gtaagagacc tctggagaag aatagttctg cagatcaatc ttccttgaag
       730        740        750        760        770        780
aaggccaaaa tatcagcttc acctacttca gtgaaaatga aacaagattc tgtcaagaaa
       790        800        810        820        830        840
gagatagatg ataagggaag ggttttggtt tcaccaaaaa tgaaagctaa acagttatct
       850        860        870        880        890        900
accagagaag atggaactga tgatgatgat gatgatgatg ttccgatatc caagagattc
       910        920        930        940        950        960
aaatcagatt cctccaacag taacacatca tctgcaaagc caaaagcagt aaaactaaat
       970        980        990       1000       1010       1020
tctacttcat cagctgcaaa gccaaaagcg agaaatgtcg tttctcctag gtccagagca
      1030       1040       1050       1060       1070       1080
atgaccaaaa acactaagaa agtaacgaag gactcaaaat attccacgtc ttcaaaatca
      1090       1100       1110       1120       1130       1140
tcaccttcct ctggagatgg gcaaaagaaa tggactactt tggtgcacaa cggtgtaata
      1150       1160       1170       1180       1190       1200
tttccaccgc catacaagcc tcatggcatt aagattttgt acaaggggaa acctgttgac
      1210       1220       1230       1240       1250       1260
ctaactattg aacaagaaga ggttgcgact atgtttgcag tgatgagaga gacagattat
      1270       1280       1290       1300       1310       1320
tatactaaac ctcaatttcg ggagaatttc tggaatgact ggcgaagact gcttggcaag
      1330       1340       1350       1360       1370       1380
aaacatgtga tacagaagtt ggatgattgt gactttactc ccatatatga gtggcatttg
      1390       1400       1410       1420       1430       1440
gaagagaaag agaagaagaa acaaatgagc acagaggaga aaaaagcttt gaaagaggag
      1450       1460       1470       1480       1490       1500
aaaatgaagc aagaggagaa atatatgtgg gctgttgttg atggtgtcaa agagaagatt
      1510       1520       1530       1540       1550       1560
ggtaatttca gagtggaacc gcctggcctt ttcagaggcc gtggagaaca tcccaagatg
      1570       1580       1590       1600       1610       1620
ggaaaactaa agaagcgtat ccatccatgc gagatcacct taaatatcgg gaaaggtgct
      1630       1640       1650       1660       1670       1680
cctattccag aatgtccaat tgctggtgaa agatggaaag aagtaaagca tgataacaca
      1690       1700       1710       1720       1730       1740
gtcacctggc tagctttctg ggctgatcct attaacccaa aagaattcaa gtatgtattt
      1750       1760       1770       1780       1790       1800
ttgggagctg gcagttctct gaaagggctg agcgacaaag agaagtacga gaaagctagg
      1810       1820       1830       1840       1850       1860
aatcttacgg atcatataga taatataaga acaacataca ccaagaattt tactgccaag
      1870       1880       1890       1900       1910       1920
gatgttaaaa tgaggcaaat tgctgtggcg acatatctca ttgataaatt ggcgcttagg
      1930       1940       1950       1960       1970       1980
gctggaaatg agaaggatga tgatgaggcc gacactgttg gttgttgtac tttaaaagtt
      1990       2000       2010       2020       2030       2040
ggaaatgtgg agtgtattcc tccaaataaa ataaagtttg attttcttgg taaggattca
      2050       2060       2070       2080       2090       2100
atccagtatg tgaacacagt cgaggttgag cctcttgttt acaaggccat tggacagttc
      2110       2120       2130       2140       2150       2160
caggcgggaa aatccaaaac agatgatctt tttgatgagt tagacacaag taaactgaat
      2170       2180       2190       2200       2210       2220
gctcatttga aggaacttgt gcctggtctc acagctaaag tattccgtac atataatgct
      2230       2240       2250       2260       2270       2280
tccatcactt tggatgaaat gctgagtcaa gaaaccaaag atggcgatgt tactcaaaaa
      2290       2300       2310       2320       2330       2340
atagtagttt atcagaaagc aaataaggag gttgccataa tctgcaatca tcagcgtact
      2350       2360       2370       2380       2390       2400
gtatcaaaga cacatggtgc gcaaattgaa aaattgactg cgagaataga agaactcaag
      2410       2420       2430       2440       2450       2460
gaggttctta aagagctcaa aactaatctt gaccgggcta aaaagggaaa accaccattg
      2470       2480       2490       2500       2510       2520
gaaggttctg atggaaagaa gattagaagc ttagaaccaa acgcgtggga gaagaagatt
      2530       2540       2550       2560       2570       2580
gctcaacaga gtgctaagat cgagaaaatg gaacgagaca tgcatacaaa agaggacttg
      2590       2600       2610       2620       2630       2640
aaaacagtgg cactgggcac gtctaagatc aactacctgg atcctagaat cacagttgca
      2650       2660       2670       2680       2690       2700
tggtgcaaac gtcatgaagt accaatcgaa aagatattca ccaagtctct tttggagaag
      2710       2720       2730       2740       2750
tttgcgtggg caatggatgt agaacccgag tacagattct cgcgccgtta g

Last modification date: Nov. 17, 2011