國立虎尾科技大學 |

DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms.

紀錄類型:	書目-語言資料,手稿 : Monograph/item
正題名/作者:	DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms./
作者:	Nagar, Shreya.
面頁冊數:	1 online resource (92 pages)
附註:	Source: Dissertations Abstracts International, Volume: 84-08, Section: B.
Contained By:	Dissertations Abstracts International84-08B.
標題:	Molecular biology. -
電子資源:	click for full text (PQDT)
ISBN:	9798371999863

DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms.
Nagar, Shreya.

DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms. - 1 online resource (92 pages)

Source: Dissertations Abstracts International, Volume: 84-08, Section: B.

Thesis (Ph.D.)--St. John's University (New York), 2023.

Includes bibliographical references

The DNA damage response (DDR) is an evolutionarily conserved process essential for cell survival. Major part of DDR is coordinated by DNA damage checkpoint (DDC). In addition to DDC, eukaryotic cells also have DNA replication checkpoint (DRC) that is distinct from the DDC and specifically signals slowly progressing or arrested replication forks. DDR involves stalling or arrest of the cell cycle, initiation of DNA repair, and altered regulation of transcription, translation, and the ubiquitin-proteasome system. DDR also triggers transcription shut-off of histone genes. One of the key outcomes of DDC/DRC activation is the increased synthesis of the deoxyribonucleoside triphosphates (dNTPs), which is a prerequisite for normal progression through the S phase and for effective DNA repair. Previously, our laboratory found that decreased histone expression activates mitochondrial electron transport chain (ETC) and oxidative metabolism, raising the question of whether the DDC/DRC also stimulate ETC. Here, we show that DDC activation in the budding yeast Saccharomyces cerevisiae, either via genetic manipulation or by growth in the presence of genotoxic chemicals, induces ETC. We observed that this induction is conferred by checkpoint kinase Rad53p-mediated inhibition of histone gene transcription and globally decreased DNA nucleosome occupancy. This globally altered chromatin structure increased the expression of genes encoding enzymes of tricarboxylic acid cycle (TCA), ETC, and oxidative phosphorylation (OXPHOS) and elevated oxygen consumption and ATP synthesis. The elevated ATP levels resulting from DDC-stimulated ETC drove the enlargement of dNTP pools; cells with a defect in ETC failed to increase dNTP synthesis and exhibited reduced fitness in the presence of DNA damage. Together, our results revealed an unexpected connection between ETC and the DDC and indicated that the benefit of increased dNTP synthesis in the face of DNA damage outweighs possible cellular damage due to increased oxygen metabolism. Unlike DDC, DRC does not inhibit transcription of histone genes but activates ETC and oxidative metabolism by a checkpoint kinase Dun1p-dependent mechanism. DRC induces transcription of RNR1-4 genes and elevates mtDNA copy number, leading to ETC activation. This mechanism contrasts with the Dun1p-independent mechanism employed by DDC, whereby DDC represses transcription of histone genes, leading to altered chromatin structure and increased expression of respiratory genes. However, since DDC also triggers Dun1p activation and increased transcription of RNR genes, it is very likely that both mechanisms function redundantly during DDC activation.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2024

Mode of access: World Wide Web

ISBN: 9798371999863Subjects--Topical Terms:

583443
Molecular biology.
Subjects--Index Terms:

DNA damage responseIndex Terms--Genre/Form:

554714
Electronic books.

DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms.
LDR:04166ntm a22004217 4500 001 1149508
005 20241022112116.5
006 m o d
007 cr bn ---uuuuu
008 250605s2023 xx obm 000 0 eng d
020 $a 9798371999863
035 $a (MiAaPQ)AAI30000114
035 $a AAI30000114
040 $a MiAaPQ $b eng $c MiAaPQ $d NTU
100 1 $a Nagar, Shreya. $3 1475774
245 1 0 $a DNA Damage Response Activates the Electron Transport Chain and Oxidative Metabolism by Two Parallel Mechanisms.
264 0 $c 2023
300 $a 1 online resource (92 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 84-08, Section: B.
500 $a Advisor: Vancura, Ales.
502 $a Thesis (Ph.D.)--St. John's University (New York), 2023.
504 $a Includes bibliographical references
520 $a The DNA damage response (DDR) is an evolutionarily conserved process essential for cell survival. Major part of DDR is coordinated by DNA damage checkpoint (DDC). In addition to DDC, eukaryotic cells also have DNA replication checkpoint (DRC) that is distinct from the DDC and specifically signals slowly progressing or arrested replication forks. DDR involves stalling or arrest of the cell cycle, initiation of DNA repair, and altered regulation of transcription, translation, and the ubiquitin-proteasome system. DDR also triggers transcription shut-off of histone genes. One of the key outcomes of DDC/DRC activation is the increased synthesis of the deoxyribonucleoside triphosphates (dNTPs), which is a prerequisite for normal progression through the S phase and for effective DNA repair. Previously, our laboratory found that decreased histone expression activates mitochondrial electron transport chain (ETC) and oxidative metabolism, raising the question of whether the DDC/DRC also stimulate ETC. Here, we show that DDC activation in the budding yeast Saccharomyces cerevisiae, either via genetic manipulation or by growth in the presence of genotoxic chemicals, induces ETC. We observed that this induction is conferred by checkpoint kinase Rad53p-mediated inhibition of histone gene transcription and globally decreased DNA nucleosome occupancy. This globally altered chromatin structure increased the expression of genes encoding enzymes of tricarboxylic acid cycle (TCA), ETC, and oxidative phosphorylation (OXPHOS) and elevated oxygen consumption and ATP synthesis. The elevated ATP levels resulting from DDC-stimulated ETC drove the enlargement of dNTP pools; cells with a defect in ETC failed to increase dNTP synthesis and exhibited reduced fitness in the presence of DNA damage. Together, our results revealed an unexpected connection between ETC and the DDC and indicated that the benefit of increased dNTP synthesis in the face of DNA damage outweighs possible cellular damage due to increased oxygen metabolism. Unlike DDC, DRC does not inhibit transcription of histone genes but activates ETC and oxidative metabolism by a checkpoint kinase Dun1p-dependent mechanism. DRC induces transcription of RNR1-4 genes and elevates mtDNA copy number, leading to ETC activation. This mechanism contrasts with the Dun1p-independent mechanism employed by DDC, whereby DDC represses transcription of histone genes, leading to altered chromatin structure and increased expression of respiratory genes. However, since DDC also triggers Dun1p activation and increased transcription of RNR genes, it is very likely that both mechanisms function redundantly during DDC activation.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2024
538 $a Mode of access: World Wide Web
650 4 $a Molecular biology. $3 583443
650 4 $a Biochemistry. $3 582831
650 4 $a Cellular biology. $3 1148666
650 4 $a Biology. $3 599573
653 $a DNA damage response
653 $a DNA damage
653 $a Electron transport chain
653 $a Replication stress
653 $a Respiration
653 $a Ribonucleotide reductase
655 7 $a Electronic books. $2 local $3 554714
690 $a 0307
690 $a 0487
690 $a 0379
690 $a 0306
710 2 $a ProQuest Information and Learning Co. $3 1178819
710 2 $a St. John's University (New York). $b CLAS Biological Sciences. $3 1475775
773 0 $t Dissertations Abstracts International $g 84-08B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=30000114 $z click for full text (PQDT)