CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability

Polynucleotide kinase phosphatase (PNKP) has enzymatic activities as 3′-phosphatase and 5′-kinase of DNA ends to promote DNA ligation and repair. Here, we show that cyclin-dependent kinases (CDKs) regulate the phosphorylation of threonine 118 (T118) in PNKP. This phosphorylation allows recruitment t...

Full description

Saved in:
Bibliographic Details
Main Authors: Kaima Tsukada, Rikiya Imamura, Tomoko Miyake, Kotaro Saikawa, Mizuki Saito, Naoya Kase, Lingyan Fu, Masamichi Ishiai, Yoshihisa Matsumoto, Mikio Shimada
Format: Article
Language:English
Published: eLife Sciences Publications Ltd 2025-03-01
Series:eLife
Subjects:
Online Access:https://elifesciences.org/articles/99217
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849389205742944256
author Kaima Tsukada
Rikiya Imamura
Tomoko Miyake
Kotaro Saikawa
Mizuki Saito
Naoya Kase
Lingyan Fu
Masamichi Ishiai
Yoshihisa Matsumoto
Mikio Shimada
author_facet Kaima Tsukada
Rikiya Imamura
Tomoko Miyake
Kotaro Saikawa
Mizuki Saito
Naoya Kase
Lingyan Fu
Masamichi Ishiai
Yoshihisa Matsumoto
Mikio Shimada
author_sort Kaima Tsukada
collection DOAJ
description Polynucleotide kinase phosphatase (PNKP) has enzymatic activities as 3′-phosphatase and 5′-kinase of DNA ends to promote DNA ligation and repair. Here, we show that cyclin-dependent kinases (CDKs) regulate the phosphorylation of threonine 118 (T118) in PNKP. This phosphorylation allows recruitment to the gapped DNA structure found in single-strand DNA (ssDNA) nicks and/or gaps between Okazaki fragments (OFs) during DNA replication. T118A (alanine)-substituted PNKP-expressing cells exhibited an accumulation of ssDNA gaps in S phase and accelerated replication fork progression. Furthermore, PNKP is involved in poly (ADP-ribose) polymerase 1 (PARP1)-dependent replication gap filling as part of a backup pathway in the absence of OFs ligation. Altogether, our data suggest that CDK-mediated PNKP phosphorylation at T118 is important for its recruitment to ssDNA gaps to proceed with OFs ligation and its backup repairs via the gap-filling pathway to maintain genome stability.
format Article
id doaj-art-6dbffeee1d30479293b4586d7b6eb6e0
institution Kabale University
issn 2050-084X
language English
publishDate 2025-03-01
publisher eLife Sciences Publications Ltd
record_format Article
series eLife
spelling doaj-art-6dbffeee1d30479293b4586d7b6eb6e02025-08-20T03:42:02ZengeLife Sciences Publications LtdeLife2050-084X2025-03-011410.7554/eLife.99217CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stabilityKaima Tsukada0https://orcid.org/0000-0002-6725-9514Rikiya Imamura1Tomoko Miyake2https://orcid.org/0000-0003-3389-4007Kotaro Saikawa3Mizuki Saito4Naoya Kase5Lingyan Fu6Masamichi Ishiai7https://orcid.org/0000-0003-4313-9945Yoshihisa Matsumoto8https://orcid.org/0000-0002-0758-290XMikio Shimada9https://orcid.org/0000-0003-1980-9187Laboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, Japan; Center for Chromosome Stability, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, DenmarkLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanNational Cancer Center Research Institute, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanLaboratory for Zero-Carbon Energy, Institute of Integrated Research, Institute of Science Tokyo, Tokyo, JapanPolynucleotide kinase phosphatase (PNKP) has enzymatic activities as 3′-phosphatase and 5′-kinase of DNA ends to promote DNA ligation and repair. Here, we show that cyclin-dependent kinases (CDKs) regulate the phosphorylation of threonine 118 (T118) in PNKP. This phosphorylation allows recruitment to the gapped DNA structure found in single-strand DNA (ssDNA) nicks and/or gaps between Okazaki fragments (OFs) during DNA replication. T118A (alanine)-substituted PNKP-expressing cells exhibited an accumulation of ssDNA gaps in S phase and accelerated replication fork progression. Furthermore, PNKP is involved in poly (ADP-ribose) polymerase 1 (PARP1)-dependent replication gap filling as part of a backup pathway in the absence of OFs ligation. Altogether, our data suggest that CDK-mediated PNKP phosphorylation at T118 is important for its recruitment to ssDNA gaps to proceed with OFs ligation and its backup repairs via the gap-filling pathway to maintain genome stability.https://elifesciences.org/articles/99217PNKPDNA replicationOkazaki fragmentDNA repair
spellingShingle Kaima Tsukada
Rikiya Imamura
Tomoko Miyake
Kotaro Saikawa
Mizuki Saito
Naoya Kase
Lingyan Fu
Masamichi Ishiai
Yoshihisa Matsumoto
Mikio Shimada
CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
eLife
PNKP
DNA replication
Okazaki fragment
DNA repair
title CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
title_full CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
title_fullStr CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
title_full_unstemmed CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
title_short CDK-mediated phosphorylation of PNKP is required for end-processing of single-strand DNA gaps on Okazaki fragments and genome stability
title_sort cdk mediated phosphorylation of pnkp is required for end processing of single strand dna gaps on okazaki fragments and genome stability
topic PNKP
DNA replication
Okazaki fragment
DNA repair
url https://elifesciences.org/articles/99217
work_keys_str_mv AT kaimatsukada cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT rikiyaimamura cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT tomokomiyake cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT kotarosaikawa cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT mizukisaito cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT naoyakase cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT lingyanfu cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT masamichiishiai cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT yoshihisamatsumoto cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability
AT mikioshimada cdkmediatedphosphorylationofpnkpisrequiredforendprocessingofsinglestranddnagapsonokazakifragmentsandgenomestability