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{{Short description|Protein-coding gene in humans}}
{{PBB|geneid=10229}}
{{Redirect|clk-1|other uses|CLK-1 (disambiguation)}}
{{Infobox_gene}}
'''Mitochondrial 5-demethoxyubiquinone hydroxylase''' ('''DMQ hydroxylase'''), also known as '''''coenzyme Q7, hydroxylase''''', is an [[enzyme]] that in humans is encoded by the ''COQ7'' [[gene]]. The ''clk-1'' (''clock-1'') gene encodes this [[protein]] that is necessary for [[ubiquinone]] biosynthesis in the worm ''[[Caenorhabditis elegans]]'' and other [[eukaryote]]s. The [[mouse]] version of the gene is called ''mclk-1'' and the human, fruit fly and yeast homolog ''COQ7'' (coenzyme Q biosynthesis protein 7).<ref name="Ewbank_1997"/><ref name="entrez">{{cite web | title = Entrez Gene: COQ7 coenzyme Q7 homolog, ubiquinone (yeast)| url = https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=10229}}</ref>


CLK-1 is not to be confused with the unrelated human protein [[CLK1]] which plays a role in [[RNA splicing]].
The '''''clk-1''''' ('''Clock abnormal protein 1''') [[gene]] encodes an [[enzyme]] ('''demethoxyubiquinone mono-oxygenase''') that is necessary for [[ubiquinone]] biosynthesis in the worm ''[[Caenorhabditis elegans]]'' and other [[eukaryote]]s. The [[mouse]] version of the gene is called '''mclk1''' and the human, fruit fly and yeast homolog '''COQ7''' (Coenzyme Q biosynthesis protein 7 homolog).<ref name="Ewbank_1997"/><ref name="entrez">{{cite web | title = Entrez Gene: COQ7 coenzyme Q7 homolog, ubiquinone (yeast)| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=10229| accessdate = }}</ref>

Clk-1 is not to be confused with the unrelated [[CLK1]] human gene which plays a role in [[RNA splicing]].


== Structure ==
== Structure ==


In 1999, [[Zoltan Vajo]] ''et al.'' cloned COQ7 from human heart. They found that the human COQ7 protein contains 179 amino acids, is mostly helical, and contains an alpha-helical membrane insertion. It has a potential N-glycosylation site, a phosphorylation site for protein kinase C and another for casein kinase II, and 3 N-myristoylation sites. Northern blot analysis detected 3 transcripts; a 1-kb transcript was predominant in heart, and a 3-kb transcript was predominant in skeletal muscle, kidney, and pancreas.<ref name="pmid10501970">{{cite journal | author = Vajo Z, King LM, Jonassen T, Wilkin DJ, Ho N, Munnich A, Clarke CF, Francomano CA | title = Conservation of the Caenorhabditis elegans timing gene clk-1 from yeast to human: a gene required for ubiquinone biosynthesis with potential implications for aging | journal = Mamm. Genome | volume = 10 | issue = 10 | pages = 1000–4 |date=October 1999 | pmid = 10501970 | doi = 10.1007/s003359901147| url = | issn = }}</ref>
The protein has two repeats of approximately 90 [[amino acid]]s, that contain two conserved motifs predicted to be important for coordination of iron. The structure and function of the gene are highly conserved among different species.<ref name="Liu_2005">{{cite journal | vauthors = Liu X, Jiang N, Hughes B, Bigras E, Shoubridge E, Hekimi S | title = Evolutionary conservation of the clk-1-dependent mechanism of longevity: loss of mclk1 increases cellular fitness and lifespan in mice | journal = Genes Dev. | volume = 19 | issue = 20 | pages = 2424–34 |date=October 2005 | pmid = 16195414 | pmc = 1257397 | doi = 10.1101/gad.1352905 }}</ref>


The protein has two repeats of about 90 [[amino acid]]s, that contain two conserved motifs. One of these DXEXXH may be part of an enzyme active site. The structure and function of the gene are highly conserved among different species.<ref name="Liu_2005">{{cite journal | author = Liu X, Jiang N, Hughes B, Bigras E, Shoubridge E, Hekimi S | title = Evolutionary conservation of the clk-1-dependent mechanism of longevity: loss of mclk1 increases cellular fitness and lifespan in mice | journal = Genes Dev. | volume = 19 | issue = 20 | pages = 2424–34 |date=October 2005 | pmid = 16195414 | pmc = 1257397 | doi = 10.1101/gad.1352905 | url = | issn = }}</ref>
The ''[[Caenorhabditis elegans|C. elegans]]'' protein contains 187 amino acid residues (20 [[kilodalton]]s), the human homolog 217 amino acid residues (24 kilodaltons, gene consisting of six [[exon]]s spanning 11 kb and located on [[chromosome 16]]).<ref name="Asaumi_1999">{{cite journal | vauthors = Asaumi S, Kuroyanagi H, Seki N, Shirasawa T | title = Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human | journal = Genomics | volume = 58 | issue = 3 | pages = 293–301 |date=June 1999 | pmid = 10373327 | doi = 10.1006/geno.1999.5838 }}</ref>


==Mitochondrial function==
The ''[[Caenorhabditis elegans|C. elegans]]'' protein contains 187 amino acid residues (20 [[kilodalton]]s), the human homolog 217 amino acid residues (24 kilodaltons, gene consisting of six [[exon]]s spanning 11 kb and located on [[chromosome 16]]).<ref name="Asaumi_1999">{{cite journal | author = Asaumi S, Kuroyanagi H, Seki N, Shirasawa T | title = Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human | journal = Genomics | volume = 58 | issue = 3 | pages = 293–301 |date=June 1999 | pmid = 10373327 | doi = 10.1006/geno.1999.5838 | url = | issn = }}</ref>
[[Ubiquinone]] is a small redox active [[lipid]] that is found in most cellular membranes where it acts as a [[Coenzyme|cofactor]] in numerous cellular redox processes, including [[mitochondria]]l [[electron transport]]. As a cofactor, ubiquinone is often involved in processes that produce [[reactive oxygen species]] (ROS). In addition, ubiquinone is one of the main endogenous antioxidants of the cell. The CLK-1 enzyme is responsible for the hydroxylation of 5-demethoxyubiquinone to 5-hydroxyubiquinone.


It has been shown that mutations in the gene are associated with increased [[life expectancy|lifespan]].<ref name="Ewbank_1997">{{cite journal | vauthors = Ewbank JJ, Barnes TM, Lakowski B, Lussier M, Bussey H, Hekimi S | title = Structural and functional conservation of the Caenorhabditis elegans timing gene clk-1 | journal = Science | volume = 275 | issue = 5302 | pages = 980–3 |date=February 1997 | pmid = 9020081 | doi = 10.1126/science.275.5302.980 | s2cid = 32191959 }}</ref><ref name="Liu_2005"/> Defects of the gene slow down a variety of developmental and physiological processes, including the cell cycle, embryogenesis, post-embryonic growth, rhythmic behaviors and aging.<ref name="Felkai_1999">{{cite journal | vauthors = Felkai S, Ewbank JJ, Lemieux J, Labbé JC, Brown GG, Hekimi S | title = CLK-1 controls respiration, behavior and aging in the nematode Caenorhabditis elegans | journal = EMBO J. | volume = 18 | issue = 7 | pages = 1783–92 |date=April 1999 | pmid = 10202142 | pmc = 1171264 | doi = 10.1093/emboj/18.7.1783 }}</ref>
==Function==
[[Ubiquinone]] is a small redox active [[lipid]] that is found in all membranes and that is a [[Co-enzyme|co-factor]] in numerous cellular redox processes, including [[mitochondria]]l [[electron transport]]. As a co-factor, ubiquinone is often involved in processes that produce [[reactive oxygen species]] (ROS). In addition, ubiquinone is one of the main endogenous antioxidants of the cell. The CLK-1 enzyme is responsible for the hydroxylation of 5-demethoxyubiquinone to 5-hydroxyubiquinone.


==Nuclear function==
When ubiquinone biosynthesis is interrupted by the absence of the enzyme, cells accumulate an intermediate of ubiquinone biosynthesis, [[demethoxyubiquinone]] (DMQ).
CLK-1 and COQ7 predominantly localise to mitochondria to participate in the ubiquinone biosynthetic pathway which is found there. However, a small pool of CLK-1 and COQ7 translocates to the nucleus in response to the production of ROS by normally functioning mitochondria in both worms and human cells, respectively.<ref>{{cite journal | vauthors = Monaghan RM, Barnes RG, Fisher K, Andreou T, Rooney N, Poulin GB, Whitmarsh AJ | title = A nuclear role for the respiratory enzyme CLK-1 in regulating mitochondrial stress responses and longevity | journal = Nature Cell Biology |date=June 2015 | pmid = 25961505 | doi = 10.1038/ncb3170 | volume=17 | issue = 6 | pages=782–92 | pmc=4539581}}</ref> Translocation of CLK-1 and COQ7 represents a mitochondrial to nuclear retrograde signalling pathway that acts to suppress mitochondrial stress responses. The mitochondrial and nuclear pools of CLK-1 are thought to contribute independently to worm lifespan regulation. The nuclear form of CLK-1 and COQ7 is thought to regulate gene expression through an unidentified mechanism.

It has been shown that mutations in the gene are associated with increased [[life expectancy|life span]].<ref name="Ewbank_1997">{{cite journal | author = Ewbank JJ, Barnes TM, Lakowski B, Lussier M, Bussey H, Hekimi S | title = Structural and functional conservation of the Caenorhabditis elegans timing gene clk-1 | journal = Science | volume = 275 | issue = 5302 | pages = 980–3 |date=February 1997 | pmid = 9020081 | doi = 10.1126/science.275.5302.980 | url = | issn = }}</ref><ref name="Liu_2005"/> Defects of the gene slow down a variety of developmental and physiological processes, including the cell cycle, embryogenesis, post-embryonic growth, rhythmic behaviors and aging.<ref name="Felkai_1999">{{cite journal | author = Felkai S, Ewbank JJ, Lemieux J, Labbé JC, Brown GG, Hekimi S | title = CLK-1 controls respiration, behavior and aging in the nematode Caenorhabditis elegans | journal = EMBO J. | volume = 18 | issue = 7 | pages = 1783–92 |date=April 1999 | pmid = 10202142 | pmc = 1171264 | doi = 10.1093/emboj/18.7.1783 | url = | issn = }}</ref>


==References==
==References==
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==Further reading==
==Further reading==
{{refbegin | 2}}
{{refbegin | 2}}
*{{cite journal | author=Maruyama K, Sugano S |title=Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. |journal=Gene |volume=138 |issue= 1-2 |pages= 171–4 |year= 1994 |pmid= 8125298 |doi=10.1016/0378-1119(94)90802-8 }}
*{{cite journal | vauthors=Maruyama K, Sugano S |title=Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. |journal=Gene |volume=138 |issue= 1–2 |pages= 171–4 |year= 1994 |pmid= 8125298 |doi=10.1016/0378-1119(94)90802-8 }}
*{{cite journal | author=Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, ''et al.'' |title=Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library. |journal=Gene |volume=200 |issue= 1-2 |pages= 149–56 |year= 1997 |pmid= 9373149 |doi=10.1016/S0378-1119(97)00411-3 }}
*{{cite journal | vauthors=Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K |title=Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library. |journal=Gene |volume=200 |issue= 1–2 |pages= 149–56 |year= 1997 |pmid= 9373149 |doi=10.1016/S0378-1119(97)00411-3 |display-authors=etal}}
*{{cite journal | author=Jonassen T, Proft M, Randez-Gil F, ''et al.'' |title=Yeast Clk-1 homologue (Coq7/Cat5) is a mitochondrial protein in coenzyme Q synthesis. |journal=J. Biol. Chem. |volume=273 |issue= 6 |pages= 3351–7 |year= 1998 |pmid= 9452453 |doi=10.1074/jbc.273.6.3351 }}
*{{cite journal | vauthors=Jonassen T, Proft M, Randez-Gil F |title=Yeast Clk-1 homologue (Coq7/Cat5) is a mitochondrial protein in coenzyme Q synthesis. |journal=J. Biol. Chem. |volume=273 |issue= 6 |pages= 3351–7 |year= 1998 |pmid= 9452453 |doi=10.1074/jbc.273.6.3351 |display-authors=etal|doi-access=free }}
*{{cite journal | author=Asaumi S, Kuroyanagi H, Seki N, Shirasawa T |title=Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human. |journal=Genomics |volume=58 |issue= 3 |pages= 293–301 |year= 1999 |pmid= 10373327 |doi= 10.1006/geno.1999.5838 }}
*{{cite journal | vauthors=Asaumi S, Kuroyanagi H, Seki N, Shirasawa T |title=Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human. |journal=Genomics |volume=58 |issue= 3 |pages= 293–301 |year= 1999 |pmid= 10373327 |doi= 10.1006/geno.1999.5838 }}
*{{cite journal | author=Vajo Z, King LM, Jonassen T, ''et al.'' |title=Conservation of the Caenorhabditis elegans timing gene clk-1 from yeast to human: a gene required for ubiquinone biosynthesis with potential implications for aging. |journal=Mamm. Genome |volume=10 |issue= 10 |pages= 1000–4 |year= 2000 |pmid= 10501970 |doi=10.1007/s003359901147 }}
*{{cite journal | vauthors=Vajo Z, King LM, Jonassen T |title=Conservation of the Caenorhabditis elegans timing gene clk-1 from yeast to human: a gene required for ubiquinone biosynthesis with potential implications for aging. |journal=Mamm. Genome |volume=10 |issue= 10 |pages= 1000–4 |year= 2000 |pmid= 10501970 |doi=10.1007/s003359901147 |s2cid=13800512 |display-authors=etal}}
*{{cite journal | author=Hartley JL, Temple GF, Brasch MA |title=DNA cloning using in vitro site-specific recombination. |journal=Genome Res. |volume=10 |issue= 11 |pages= 1788–95 |year= 2001 |pmid= 11076863 |doi=10.1101/gr.143000 | pmc=310948 }}
*{{cite journal | vauthors=Hartley JL, Temple GF, Brasch MA |title=DNA cloning using in vitro site-specific recombination. |journal=Genome Res. |volume=10 |issue= 11 |pages= 1788–95 |year= 2001 |pmid= 11076863 |doi=10.1101/gr.143000 | pmc=310948 }}
*{{cite journal | author=Wiemann S, Weil B, Wellenreuther R, ''et al.'' |title=Toward a catalog of human genes and proteins: sequencing and analysis of 500 novel complete protein coding human cDNAs. |journal=Genome Res. |volume=11 |issue= 3 |pages= 422–35 |year= 2001 |pmid= 11230166 |doi= 10.1101/gr.GR1547R | pmc=311072 }}
*{{cite journal | vauthors=Wiemann S, Weil B, Wellenreuther R |title=Toward a catalog of human genes and proteins: sequencing and analysis of 500 novel complete protein coding human cDNAs. |journal=Genome Res. |volume=11 |issue= 3 |pages= 422–35 |year= 2001 |pmid= 11230166 |doi= 10.1101/gr.GR1547R | pmc=311072 |display-authors=etal}}
*{{cite journal | author=Simpson JC, Wellenreuther R, Poustka A, ''et al.'' |title=Systematic subcellular localization of novel proteins identified by large-scale cDNA sequencing. |journal=EMBO Rep. |volume=1 |issue= 3 |pages= 287–92 |year= 2001 |pmid= 11256614 |doi= 10.1093/embo-reports/kvd058 | pmc=1083732 }}
*{{cite journal | vauthors=Simpson JC, Wellenreuther R, Poustka A |title=Systematic subcellular localization of novel proteins identified by large-scale cDNA sequencing. |journal=EMBO Rep. |volume=1 |issue= 3 |pages= 287–92 |year= 2001 |pmid= 11256614 |doi= 10.1093/embo-reports/kvd058 | pmc=1083732 |display-authors=etal}}
*{{cite journal | author=Stenmark P, Grünler J, Mattsson J, ''et al.'' |title=A new member of the family of di-iron carboxylate proteins. Coq7 (clk-1), a membrane-bound hydroxylase involved in ubiquinone biosynthesis. |journal=J. Biol. Chem. |volume=276 |issue= 36 |pages= 33297–300 |year= 2001 |pmid= 11435415 |doi= 10.1074/jbc.C100346200 }}
*{{cite journal | vauthors=Stenmark P, Grünler J, Mattsson J |title=A new member of the family of di-iron carboxylate proteins. Coq7 (clk-1), a membrane-bound hydroxylase involved in ubiquinone biosynthesis. |journal=J. Biol. Chem. |volume=276 |issue= 36 |pages= 33297–300 |year= 2001 |pmid= 11435415 |doi= 10.1074/jbc.C100346200 |display-authors=etal|doi-access=free }}
*{{cite journal | author=Takahashi M, Asaumi S, Honda S, ''et al.'' |title=Mouse coq7/clk-1 orthologue rescued slowed rhythmic behavior and extended life span of clk-1 longevity mutant in Caenorhabditis elegans. |journal=Biochem. Biophys. Res. Commun. |volume=286 |issue= 3 |pages= 534–40 |year= 2001 |pmid= 11511092 |doi= 10.1006/bbrc.2001.5439 }}
*{{cite journal | vauthors=Takahashi M, Asaumi S, Honda S |title=Mouse coq7/clk-1 orthologue rescued slowed rhythmic behavior and extended life span of clk-1 longevity mutant in Caenorhabditis elegans. |journal=Biochem. Biophys. Res. Commun. |volume=286 |issue= 3 |pages= 534–40 |year= 2001 |pmid= 11511092 |doi= 10.1006/bbrc.2001.5439 |display-authors=etal}}
*{{cite journal | author=Rea S |title=CLK-1/Coq7p is a DMQ mono-oxygenase and a new member of the di-iron carboxylate protein family. |journal=FEBS Lett. |volume=509 |issue= 3 |pages= 389–94 |year= 2002 |pmid= 11749961 |doi=10.1016/S0014-5793(01)03099-X }}
*{{cite journal | author=Rea S |title=CLK-1/Coq7p is a DMQ mono-oxygenase and a new member of the di-iron carboxylate protein family. |journal=FEBS Lett. |volume=509 |issue= 3 |pages= 389–94 |year= 2002 |pmid= 11749961 |doi=10.1016/S0014-5793(01)03099-X |s2cid=28650687 |doi-access=free }}
*{{cite journal | author=Strausberg RL, Feingold EA, Grouse LH, ''et al.'' |title=Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=99 |issue= 26 |pages= 16899–903 |year= 2003 |pmid= 12477932 |doi= 10.1073/pnas.242603899 | pmc=139241 }}
*{{cite journal | vauthors=Strausberg RL, Feingold EA, Grouse LH |title=Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=99 |issue= 26 |pages= 16899–903 |year= 2003 |pmid= 12477932 |doi= 10.1073/pnas.242603899 | pmc=139241 |bibcode=2002PNAS...9916899M |display-authors=etal|doi-access=free }}
*{{cite journal | author=Ota T, Suzuki Y, Nishikawa T, ''et al.'' |title=Complete sequencing and characterization of 21,243 full-length human cDNAs. |journal=Nat. Genet. |volume=36 |issue= 1 |pages= 40–5 |year= 2004 |pmid= 14702039 |doi= 10.1038/ng1285 }}
*{{cite journal | vauthors=Ota T, Suzuki Y, Nishikawa T |title=Complete sequencing and characterization of 21,243 full-length human cDNAs. |journal=Nat. Genet. |volume=36 |issue= 1 |pages= 40–5 |year= 2004 |pmid= 14702039 |doi= 10.1038/ng1285 |display-authors=etal|doi-access=free }}
*{{cite journal | author=Wiemann S, Arlt D, Huber W, ''et al.'' |title=From ORFeome to biology: a functional genomics pipeline. |journal=Genome Res. |volume=14 |issue= 10B |pages= 2136–44 |year= 2004 |pmid= 15489336 |doi= 10.1101/gr.2576704 | pmc=528930 }}
*{{cite journal | vauthors=Wiemann S, Arlt D, Huber W |title=From ORFeome to biology: a functional genomics pipeline. |journal=Genome Res. |volume=14 |issue= 10B |pages= 2136–44 |year= 2004 |pmid= 15489336 |doi= 10.1101/gr.2576704 | pmc=528930 |display-authors=etal}}
*{{cite journal | author=Mehrle A, Rosenfelder H, Schupp I, ''et al.'' |title=The LIFEdb database in 2006. |journal=Nucleic Acids Res. |volume=34 |issue= Database issue |pages= D415–8 |year= 2006 |pmid= 16381901 |doi= 10.1093/nar/gkj139 | pmc=1347501 }}
*{{cite journal | vauthors=Mehrle A, Rosenfelder H, Schupp I |title=The LIFEdb database in 2006. |journal=Nucleic Acids Res. |volume=34 |issue= Database issue |pages= D415–8 |year= 2006 |pmid= 16381901 |doi= 10.1093/nar/gkj139 | pmc=1347501 |display-authors=etal}}
{{refend}}
{{refend}}


== External links ==
== External links ==
{{Portal|Biology}}
* {{UCSC genome browser|COQ7}}
* {{UCSC genome browser|COQ7}}
* {{UCSC gene details|COQ7}}
* {{UCSC gene details|COQ7}}


{{Monooxygenases}}
[[Category:Caenorhabditis elegans genes]]
{{Enzymes}}

[[Category:EC 1.13]]
[[Category:EC 1.13]]
[[Category:Ageing]]
[[Category:Ageing]]

Latest revision as of 05:24, 18 September 2023

COQ7
Identifiers
AliasesCOQ7, CAT5, CLK-1, CLK1, COQ10D8, coenzyme Q7, hydroxylase
External IDsOMIM: 601683; MGI: 107207; HomoloGene: 6953; GeneCards: COQ7; OMA:COQ7 - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_001190983
NM_016138

NM_009940
NM_001304758

RefSeq (protein)

NP_001291687
NP_034070

Location (UCSC)Chr 16: 19.07 – 19.08 MbChr 7: 118.11 – 118.13 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Mitochondrial 5-demethoxyubiquinone hydroxylase (DMQ hydroxylase), also known as coenzyme Q7, hydroxylase, is an enzyme that in humans is encoded by the COQ7 gene. The clk-1 (clock-1) gene encodes this protein that is necessary for ubiquinone biosynthesis in the worm Caenorhabditis elegans and other eukaryotes. The mouse version of the gene is called mclk-1 and the human, fruit fly and yeast homolog COQ7 (coenzyme Q biosynthesis protein 7).[5][6]

CLK-1 is not to be confused with the unrelated human protein CLK1 which plays a role in RNA splicing.

Structure

[edit]

The protein has two repeats of approximately 90 amino acids, that contain two conserved motifs predicted to be important for coordination of iron. The structure and function of the gene are highly conserved among different species.[7]

The C. elegans protein contains 187 amino acid residues (20 kilodaltons), the human homolog 217 amino acid residues (24 kilodaltons, gene consisting of six exons spanning 11 kb and located on chromosome 16).[8]

Mitochondrial function

[edit]

Ubiquinone is a small redox active lipid that is found in most cellular membranes where it acts as a cofactor in numerous cellular redox processes, including mitochondrial electron transport. As a cofactor, ubiquinone is often involved in processes that produce reactive oxygen species (ROS). In addition, ubiquinone is one of the main endogenous antioxidants of the cell. The CLK-1 enzyme is responsible for the hydroxylation of 5-demethoxyubiquinone to 5-hydroxyubiquinone.

It has been shown that mutations in the gene are associated with increased lifespan.[5][7] Defects of the gene slow down a variety of developmental and physiological processes, including the cell cycle, embryogenesis, post-embryonic growth, rhythmic behaviors and aging.[9]

Nuclear function

[edit]

CLK-1 and COQ7 predominantly localise to mitochondria to participate in the ubiquinone biosynthetic pathway which is found there. However, a small pool of CLK-1 and COQ7 translocates to the nucleus in response to the production of ROS by normally functioning mitochondria in both worms and human cells, respectively.[10] Translocation of CLK-1 and COQ7 represents a mitochondrial to nuclear retrograde signalling pathway that acts to suppress mitochondrial stress responses. The mitochondrial and nuclear pools of CLK-1 are thought to contribute independently to worm lifespan regulation. The nuclear form of CLK-1 and COQ7 is thought to regulate gene expression through an unidentified mechanism.

References

[edit]
  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000167186Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000030652Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ a b Ewbank JJ, Barnes TM, Lakowski B, Lussier M, Bussey H, Hekimi S (February 1997). "Structural and functional conservation of the Caenorhabditis elegans timing gene clk-1". Science. 275 (5302): 980–3. doi:10.1126/science.275.5302.980. PMID 9020081. S2CID 32191959.
  6. ^ "Entrez Gene: COQ7 coenzyme Q7 homolog, ubiquinone (yeast)".
  7. ^ a b Liu X, Jiang N, Hughes B, Bigras E, Shoubridge E, Hekimi S (October 2005). "Evolutionary conservation of the clk-1-dependent mechanism of longevity: loss of mclk1 increases cellular fitness and lifespan in mice". Genes Dev. 19 (20): 2424–34. doi:10.1101/gad.1352905. PMC 1257397. PMID 16195414.
  8. ^ Asaumi S, Kuroyanagi H, Seki N, Shirasawa T (June 1999). "Orthologues of the Caenorhabditis elegans longevity gene clk-1 in mouse and human". Genomics. 58 (3): 293–301. doi:10.1006/geno.1999.5838. PMID 10373327.
  9. ^ Felkai S, Ewbank JJ, Lemieux J, Labbé JC, Brown GG, Hekimi S (April 1999). "CLK-1 controls respiration, behavior and aging in the nematode Caenorhabditis elegans". EMBO J. 18 (7): 1783–92. doi:10.1093/emboj/18.7.1783. PMC 1171264. PMID 10202142.
  10. ^ Monaghan RM, Barnes RG, Fisher K, Andreou T, Rooney N, Poulin GB, Whitmarsh AJ (June 2015). "A nuclear role for the respiratory enzyme CLK-1 in regulating mitochondrial stress responses and longevity". Nature Cell Biology. 17 (6): 782–92. doi:10.1038/ncb3170. PMC 4539581. PMID 25961505.

Further reading

[edit]
[edit]