Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai – 625 021, India.
Research Article
World Journal of Advanced Research and Reviews, 2024, 23(02), 2239-2260
Received on 17 July 2024; Revised on 24 August 2024; Accepted on 26 August 2024
In eukaryotes, genome replication starts with the initiation of replication by the primases, followed by the synthesis of the leading- and lagging-strands by two different replicative DNA polymerases (pols), viz. ε and δ, respectively. The polymerase and proofreading (PR) active sites of the δ pols are analyzed from various animal and plant sources by multiple sequence alignment (MSA). The animal and plant δ pols are found to possess almost identical polymerase and PR domains. However, the BLASTp analysis has shown only 56.57% identity between the plant (Arabidopsis thaliana) and animal (human) δ pols. The template-binding pair (–YG-), the catalytic amino acid (K) and the nucleotide selection amino acid (Q) are found to be the same in both plant and animal δ pols. The δ pols from plant and animal sources contain a typical Mg2+-binding motif, (-YGDTD-) in the polymerase domain and 2 possible Zn2+-binding motifs (ZBMs) in their carboxy terminal domain (CTD). One of the ZBMs binds to the 4Fe-4S cluster and is suggested to be involved in the regulation of replication. Interestingly, the invariant –SLYPS- and -YGDTD- motifs which are found in the δ pols are not found in the other replicative pol ε. Furthermore, both animal and plant δ pols use the same PR exonuclease active site amino acids, and thus, belong to the DEDD(Y)-superfamily of exonucleases, as found in other DNA pols. Besides, many specialized, conserved sequence motifs are also identified and discussed.
Eukaryotic genome replication; DNA polymerases δ; δ DNA polymerase active site; Proofreading exonucleases; Proofreading exonuclease active sites; Arabidopsis thaliana; Homo sapiens
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Peramachi Palanivelu. Replicative δ Polymerases from Plants and Animals Possess Very Similar Polymerase, Proofreading and Regulatory Domains. World Journal of Advanced Research and Reviews, 2024, 23(2), 2239-2260. Article DOI: https://doi.org/10.30574/wjarr.2024.23.2.2590