DNA polymerase (Dpo) reads a DNA strand and catalyzes the synthesis of its complementary strand. Dpo's are divided into 7 families according to their sequence homology and 3D structure similarities.[1] The families are:
- Family A - replicative or repair Dpo.
- Family B - replicative Dpo involved in processing DNA replication during cell division (includes eukaryotic Dpo α,δ,ε).
- Family C - major replicative Dpo in bacteria (includes Dpo II, III, IV).
- Family D - replicative. Present in archaea.
- Family X - eukaryotic repair Dpo (includes Dpo β,λ,σ,μ and terminal deoxynucleotidyl transferase).
- Family Y - replicative of damaged DNA (includes eukaryotic η,ι,κ).
- Family RT - reverse transcriptase. See Reverse transcriptase.
Some Dpo terminology:
Dpo sliding clamp is made of the complex of Dpo and Proliferating Cell Nuclear Antigen (PCNA) which encircles it.
The BRCT domain in Dpo is the C-terminal domain of breast cancer susceptibility protein.
Klenow fragment is a large Dpo fragment produced upon cleavage of Dpo by subtilisin.
In the E. coli, the EcDpo III subunits β, γ, δ, δ' are named clamp loader. This complex assembles the β subunit sliding clamp unto the DNA.
Prokaryotic DNA polymerases:
Eukaryotic DNA polymerases:
- Pol α,β,γ,δ,ε,ζ,η,ι,κ. See also DNA polymerase beta.
- Rev1 is a Dpo involved in replication over DNA lesions.
- Terminal deoxynucleotidyl transferase (TdT) is a family X Dpo expressed in immature lymphoid cells. TdT adds nucleotides to exons during antibody gene recombination.
in Family A DNA polymerase I (1taq).
See also User:Karl E. Zahn/RB69 DNA polymerase (gp43)
