P09838 · TDT_MOUSE

  • Protein
    DNA nucleotidylexotransferase
  • Gene
    Dntt
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Isoform TDT-S

Transferase that catalyzes the nontemplated addition of nucleoside triphosphate to coding ends during V(D)J recombination (N addition). Involved in the generation of diversity in the antigen-binding region of immunoglobulin heavy and light chains and T-cell receptors during B- and T-cell development. Does not act on double-stranded DNA with blunt ends.

Isoform TDT-L

3'-to-5' DNA exonuclease. Involved in the generation of diversity in the antigen-binding region of immunoglobulin heavy and light chains and T-cell receptors during B- and T-cell development. Acts on single-stranded and double-stranded DNA with 3' or 5' extensions, but not on double-stranded DNA with blunt ends. Attenuates not only isoform TDT-S-catalyzed N addition, but also P (palindromic) addition in coding joins (PubMed:11938351).
Lacks terminal transferase activity (PubMed:11136823, PubMed:7556063).

Catalytic activity

Cofactor

Mg2+ (UniProtKB | Rhea| CHEBI:18420 )

Note: Can also utilize other divalent cations, such as Mn2+ and Co2+ (in vitro).

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
300 μMdATP35
In assays with isoform TDT-S.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site333-338a 2'-deoxyribonucleoside 5'-triphosphate (UniProtKB | ChEBI)
Binding site342-345a 2'-deoxyribonucleoside 5'-triphosphate (UniProtKB | ChEBI)
Binding site343Mg2+ (UniProtKB | ChEBI)
Binding site345Mg2+ (UniProtKB | ChEBI)
Binding site434Mg2+ (UniProtKB | ChEBI)
Binding site449-450a 2'-deoxyribonucleoside 5'-triphosphate (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentchromatin
Cellular Componentcytosol
Cellular Componenteuchromatin
Cellular Componentnuclear matrix
Cellular Componentnucleoplasm
Cellular Componentnucleus
Molecular FunctionDNA binding
Molecular FunctionDNA nucleotidylexotransferase activity
Molecular FunctionDNA-directed DNA polymerase activity
Molecular Functionhydrolase activity
Molecular Functionmetal ion binding
Biological ProcessDNA metabolic process
Biological ProcessDNA modification
Biological Processdouble-strand break repair via nonhomologous end joining
Biological Processresponse to ATP

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    DNA nucleotidylexotransferase
  • EC number
  • Alternative names
    • Terminal addition enzyme
    • Terminal deoxynucleotidyltransferase
      (TDT; Terminal transferase)

Gene names

    • Name
      Dntt
    • Synonyms
      Tdt

Organism names

  • Taxonomic identifier
  • Strains
    • BALB/cJ
    • C57BL/6J
    • NOD
    • OF1
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Glires > Rodentia > Myomorpha > Muroidea > Muridae > Murinae > Mus > Mus

Accessions

  • Primary accession
    P09838
  • Secondary accessions
    • Q99PD0
    • Q99PD1

Proteomes

Organism-specific databases

Subcellular Location

Isoform TDT-S

Nucleus

Isoform TDT-L

Nucleus
Cytoplasm
Note: The subcellular location is controversial. Detected in the nucleus (PubMed:11136823).
Found mainly in the cytoplasm (PubMed:7556063).

Keywords

Phenotypes & Variants

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis29Almost complete loss of exonuclease activity in TDT-L; when associated with A-170 and A-473. Decreased transferase activity in TDT-S; when associated with A-170 and A-473.
Mutagenesis170Almost complete loss of exonuclease activity in TDT-L; when associated with A-29 and A-473. Decreased transferase activity in TDT-S; when associated with A-29 and A-473.
Mutagenesis342Nearly abolishes enzyme activity.
Mutagenesis398Nearly abolishes enzyme activity.
Mutagenesis399Nearly abolishes enzyme activity.
Mutagenesis400Reduces enzyme activity.
Mutagenesis403Nearly abolishes enzyme activity.
Mutagenesis473Almost complete loss of exonuclease activity in TDT-L; when associated with A-29 and A-170. Decreased transferase activity in TDT-S; when associated with A-29 and A-170.
Mutagenesis473Nearly abolishes enzyme activity.
Mutagenesis475Nearly abolishes enzyme activity.

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 27 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

PTM/Processing

Features

Showing features for chain, modified residue.

TypeIDPosition(s)Description
ChainPRO_00002187921-510DNA nucleotidylexotransferase
Modified residue134Phosphoserine

Keywords

Proteomic databases

PTM databases

Expression

Tissue specificity

Isoform TDT-L: Expressed in the thymus, and, at lower levels, in the bone marrow (PubMed:11136823, PubMed:7556063, PubMed:8464703).
Detected in both cycling and noncycling pro-B and pre-B cells (at protein level) (PubMed:11938351).
Isoform TDT-S: Expressed in both cycling and noncycling pro-B, but not pre-B, cells (at protein level) (PubMed:11938351).
Not detected in mature peripheral or germinal center B cells (PubMed:11938351).

Gene expression databases

Interaction

Subunit

Interacts with PRP19 and DNTTIP1. Forms a ternary complex with DNTTIP2 and core histone. Released from this complex by PCNA. Interacts with TRERF1.

Protein-protein interaction databases

Miscellaneous

Family & Domains

Features

Showing features for region, motif, domain.

TypeIDPosition(s)Description
Region1-22Disordered
Motif11-17Nuclear localization signal
Domain27-124BRCT
Region151-510Mediates interaction with DNTTIP2
Region258-262Involved in DNA binding

Sequence similarities

Belongs to the DNA polymerase type-X family.

Phylogenomic databases

Family and domain databases

Sequence & Isoform

Align isoforms (2)
  • Sequence status
    Complete

This entry describes 2 isoforms produced by Alternative splicing.

P09838-2

This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

  • Name
    TDT-S
  • Synonyms
    TDT-Small, TdtS
  • Note
    Major form in the thymus and the bone marrow (PubMed:11136823, PubMed:8464703).
    Catalyzes the nontemplated addition of nucleoside triphosphate to coding ends during V(D)J recombination (PubMed:23856622).
    May have a longer half-life than isoform TDT-L (PubMed:7556063).
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Length
    510
  • Mass (Da)
    58,266
  • Last updated
    2018-12-05 v4
  • Checksum
    CF6E850EE36EE3BF
MDPLQAVHLGPRKKRPRQLGTPVASTPYDIRFRDLVLFILEKKMGTTRRAFLMELARRKGFRVENELSDSVTHIVAENNSGSDVLEWLQLQNIKASSELELLDISWLIECMGAGKPVEMMGRHQLVVNRNSSPSPVPGSQNVPAPAVKKISQYACQRRTTLNNYNQLFTDALDILAENDELRENEGSCLAFMRASSVLKSLPFPITSMKDTEGIPCLGDKVKSIIEGIIEDGESSEAKAVLNDERYKSFKLFTSVFGVGLKTAEKWFRMGFRTLSKIQSDKSLRFTQMQKAGFLYYEDLVSCVNRPEAEAVSMLVKEAVVTFLPDALVTMTGGFRRGKMTGHDVDFLITSPEATEDEEQQLLHKVTDFWKQQGLLLYCDILESTFEKFKQPSRKVDALDHFQKCFLILKLDHGRVHSEKSGQQEGKGWKAIRVDLVMCPYDRRAFALLGWTGSRQFERDLRRYATHERKMMLDNHALYDRTKRVFLEAESEEEIFAHLGLDYIEPWERNA

P09838-1

  • Name
    TDT-L
  • Synonyms
    TDT-Large, TdtL
  • Note
    Exhibits 3'-to-5' DNA exonuclease activity (EC=3.1.11.-) (PubMed:23856622).
    May have a shorter half-life than isoform TDT-S (PubMed:10878023, PubMed:7556063).
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical
    • 482-482: K → KGKTVTISPLDGKVSKLQKAL

Features

Showing features for sequence conflict, alternative sequence.

TypeIDPosition(s)Description
Sequence conflict26in Ref. 2; CAA48634
Sequence conflict99in Ref. 2; CAA48634
Sequence conflict193in Ref. 1; CAA27735
Sequence conflict287in Ref. 1; CAA27735
Sequence conflict309in Ref. 1; CAA27735
Sequence conflict367in Ref. 1; CAA27735
Sequence conflict441-445in Ref. 1; CAA27735
Alternative sequenceVSP_059967482in isoform TDT-L

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
X04123
EMBL· GenBank· DDBJ
CAA27735.1
EMBL· GenBank· DDBJ
mRNA
X68670
EMBL· GenBank· DDBJ
CAA48634.2
EMBL· GenBank· DDBJ
mRNA
AF316014
EMBL· GenBank· DDBJ
AAK07884.1
EMBL· GenBank· DDBJ
mRNA
AF316015
EMBL· GenBank· DDBJ
AAK07885.1
EMBL· GenBank· DDBJ
mRNA
AK087978
EMBL· GenBank· DDBJ
BAC40071.1
EMBL· GenBank· DDBJ
mRNA
AK088709
EMBL· GenBank· DDBJ
BAC40518.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

Disclaimer

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