Page last updated: 2024-10-24
DNA replication initiation
Definition
Target type: biologicalprocess
The process in which DNA-dependent DNA replication is started; it begins when specific sequences, known as origins of replication, are recognized and bound by the origin recognition complex, followed by DNA unwinding. [PMID:28209641]
DNA replication initiation is a complex and tightly regulated process that sets the stage for the duplication of the entire genome. It involves a series of orchestrated events, beginning with the recognition of the origin of replication (ori) on the DNA molecule.
The process starts with the binding of initiator proteins to specific DNA sequences at the ori. These initiator proteins are typically multi-subunit complexes, and in eukaryotes, they are known as Origin Recognition Complexes (ORCs). ORCs bind to specific DNA sequences, marking the beginning of the replication origin.
Once bound, ORCs recruit other proteins to the origin, forming a pre-replication complex (pre-RC). This complex includes proteins like Cdc6 and Cdt1, which facilitate the loading of the crucial DNA helicase enzyme, MCM2-7.
The MCM2-7 helicase is a ring-shaped complex that will ultimately unwind the DNA strands during replication. Its loading onto the DNA is a critical step, ensuring that replication occurs only once per cell cycle.
The transition from the pre-RC to the active replication fork requires further steps, including the activation of the pre-RC by phosphorylation, mediated by cyclin-dependent kinases (CDKs). This activation triggers the recruitment of additional proteins, including DNA polymerase and other replication factors.
Finally, the activation of the MCM2-7 helicase, fueled by ATP hydrolysis, initiates the unwinding of the DNA double helix, creating two single-stranded DNA templates. These templates are then used by DNA polymerase to synthesize new complementary DNA strands, leading to the replication of the entire genome.
DNA replication initiation is a highly regulated process, ensuring that DNA replication occurs only once per cell cycle and that each daughter cell receives a complete copy of the genome. The intricate interplay of proteins and the precise control of various enzymatic activities guarantee the fidelity and accuracy of this fundamental biological process.'
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Proteins (3)
| Protein | Definition | Taxonomy |
|---|---|---|
| G1/S-specific cyclin-E1 | A G1/S-specific cyclin-E1 that is encoded in the genome of human. [PRO:DNx] | Homo sapiens (human) |
| DNA polymerase alpha catalytic subunit | A DNA polymerase alpha catalytic subunit that is encoded in the genome of human. [PRO:DNx] | Homo sapiens (human) |
| G1/S-specific cyclin-E2 | A G1/S-specific cyclin-E2 that is encoded in the genome of human. [PRO:DNx] | Homo sapiens (human) |
Compounds (81)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| digallic acid | digallic acid: structure given in first source | benzoate ester; gallate ester | |
| tyrphostin a23 | tyrphostin A23: inhibits EGF-stimulated thymidine incorporation as well as EGF-stimulated receptor autophosphorylation & tyrosine phosphorylation & cell proliferation; structure given in first source | catechols | |
| bisindolylmaleimide i | bisindolylmaleimide I: a bis(indolyl)maleimide | ||
| bisindolylmaleimide iv | indoles; maleimides | ||
| bohemine | bohemine : Purine substituted on C-2, C-6 and N-9 with (3-hydroxypropyl)amino, benzylamino and isopropyl groups respectively; a synthetic, cell-permeable, cyclin-dependent kinase (CDK) inhibitor that is structurally similar to olomoucine and roscovitine. | purines | EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| n(6),n(6)-dimethyladenine | N(6),N(6)-dimethyladenine : A tertiary amine that is adenine substituted at N-6 by geminal methyl groups. | tertiary amine | |
| foscarnet | Foscarnet: An antiviral agent used in the treatment of cytomegalovirus retinitis. Foscarnet also shows activity against human herpesviruses and HIV. phosphonoformic acid : Phosphoric acid in which one of the hydroxy groups is replaced by a carboxylic acid group. It is used as the trisodium salt as an antiviral agent in the treatment of cytomegalovirus retinitis (CMV retinitis, an inflamation of the retina that can lead to blindness) and as an alternative to ganciclovir for AIDS patients who require concurrent antiretroviral therapy but are unable to tolerate ganciclovir due to haematological toxicity. | carboxylic acid; one-carbon compound; phosphonic acids | antiviral drug; geroprotector; HIV-1 reverse transcriptase inhibitor; sodium-dependent Pi-transporter inhibitor |
| gw8510 | GW8510: 3' substituted indolone as a scaffold for the development of neuroprotective drug; structure in first source | ||
| indirubin-3'-monoxime | indirubin-3'-monoxime : A member of the class of biindoles that is indirubin in which the keto group at position 3' has undergone condensation with hydroxylamine to form the corresponding oxime. indirubin-3'-monoxime: has antiangiogenic activity | ||
| staurosporine aglycone | staurosporine aglycone: metabolite from culture broth of Nocardiopsis sp.; a neurotrophin antag; inhibits BDNF TrkB receptor | ||
| nu6102 | NU6102: structure in first source | ||
| olomoucine | olomoucine : A 9H-purine that is substituted by a (2-hydroxyethyl)nitrilo, benzylnitrilo and a methyl group at positions 2,6 and 9, respectively. It is a cyclin-dependent kinase inhibitor. olomoucine: inhibits protein P34CDC2 | 2,6-diaminopurines; ethanolamines | EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| imatinib | aromatic amine; benzamides; N-methylpiperazine; pyridines; pyrimidines | antineoplastic agent; apoptosis inducer; tyrosine kinase inhibitor | |
| indirubin | |||
| indigo | hydroxyindoles | ||
| staurosporine | indolocarbazole alkaloid; organic heterooctacyclic compound | apoptosis inducer; bacterial metabolite; EC 2.7.11.13 (protein kinase C) inhibitor; geroprotector | |
| zidovudine triphosphate | |||
| fascaplysine | fascaplysine: from tropic sea sponges | ||
| LSM-4272 | beta-carbolines | ||
| dehydroabietic acid | dehydroabietate : A monocarboxylic acid anion that is the conjugate base of dehydroabietic acid, obtained by deprotonation of the carboxy group. dehydroabietic acid : An abietane diterpenoid that is abieta-8,11,13-triene substituted at position 18 by a carboxy group. dehydroabietic acid: major aquatic toxicant in effluent of pulp and paper mills | abietane diterpenoid; carbotricyclic compound; monocarboxylic acid | allergen; metabolite |
| birb 796 | aromatic ether; morpholines; naphthalenes; pyrazoles; ureas | EC 2.7.11.24 (mitogen-activated protein kinase) inhibitor; immunomodulator | |
| cyc 202 | seliciclib : 2,6-Diaminopurine carrying benzylamino, (2R)-1-hydroxybutan-2-yl and isopropyl substituents at C-6, C-2-N and N-9 respectively. It is an experimental drug candidate in the family of pharmacological cyclin-dependent kinase (CDK) inhibitors. | 2,6-diaminopurines | antiviral drug; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| lapatinib | furans; organochlorine compound; organofluorine compound; quinazolines | antineoplastic agent; tyrosine kinase inhibitor | |
| 2H-pyrazolo[4,3-b]quinoxalin-3-amine | quinoxaline derivative | ||
| resveratrol | trans-resveratrol : A resveratrol in which the double bond has E configuration. | resveratrol | antioxidant; phytoalexin; plant metabolite; quorum sensing inhibitor; radical scavenger |
| 7-n-butyl-6-(4'-hydroxyphenyl)-5h-pyrrolo(2,3b)pyrazine | |||
| 6-bromoindirubin-3'-oxime | 6-bromoindirubin-3'-oxime : A member of the class of biindoles that is indirubin substituted at position 6 by a bromo group and in which the keto group at position 3' has undergone condensation with hydroxylamine to form the corresponding oxime. 6-bromoindirubin-3'-oxime: structure in first source | ||
| purvalanol b | purvalanol B: protein kinase inhibitor; structure in first source | purvalanol | protein kinase inhibitor |
| repsox | RepSox: inhibits TGF-beta signaling; structure in first source appears to be incorrect | pyrazolopyridine | |
| TTP | pyrimidine ribonucleoside 5'-triphosphate | ||
| purvalanol a | 6-((3-chloro)anilino)-2-(isopropyl-2-hydroxyethylamino)-9-isopropylpurine: purvalanol A is the (1R)-isomer; | purvalanol | |
| aphidicolin | aphidicolin : A tetracyclic diterpenoid that has an tetradecahydro-8,11a-methanocyclohepta[a]naphthalene skeleton with two hydroxymethyl substituents at positions 4 and 9, two methyl substituents at positions 4 and 11b and two hydroxy substituents at positions 3 and 9. An antibiotic with antiviral and antimitotical properties. Aphidicolin is a reversible inhibitor of eukaryotic nuclear DNA replication. Aphidicolin: An antiviral antibiotic produced by Cephalosporium aphidicola and other fungi. It inhibits the growth of eukaryotic cells and certain animal viruses by selectively inhibiting the cellular replication of DNA polymerase II or the viral-induced DNA polymerases. The drug may be useful for controlling excessive cell proliferation in patients with cancer, psoriasis or other dermatitis with little or no adverse effect upon non-multiplying cells. | tetracyclic diterpenoid | antimicrobial agent; antimitotic; antineoplastic agent; antiviral drug; apoptosis inducer; Aspergillus metabolite; DNA synthesis inhibitor; EC 2.7.7.7 (DNA-directed DNA polymerase) inhibitor; fungal metabolite |
| 2-methyl-5-(4-methylanilino)-1,3-benzothiazole-4,7-dione | aminotoluene | ||
| pnu183792 | PNU183792: structure in first source | ||
| cgp 60474 | substituted aniline | ||
| cgp 74514a | |||
| 1,4-dimethoxy-10H-acridine-9-thione | acridines | ||
| bms 387032 | N-(5-(((5-(1,1-dimethylethyl)-2-oxazolyl)methyl)thio)-2-thiazolyl)-4-piperidinecarboxamide: a CDK2 inhibitor with antineoplastic activity; structure in first source N-(5-{[(5-tert-butyl-1,3-oxazol-2-yl)methyl]sulfanyl}-1,3-thiazol-2-yl)piperidine-4-carboxamide : A secondary carboxamide resulting from the formal condensation of the carboxy group of piperidine-4-carboxylic acid with the amino group of 5-{[(5-tert-butyl-1,3-oxazol-2-yl)methyl]sulfanyl}-1,3-thiazol-2-amine. It is an ATP-competitive inhibitor of CDK2, CDK7 and CDK9 kinases and exhibits anti-cancer properties. | 1,3-oxazoles; 1,3-thiazoles; organic sulfide; piperidinecarboxamide; secondary carboxamide | angiogenesis inhibitor; antineoplastic agent; apoptosis inducer; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| sf 2370 | K-252a : A organic heterooctacyclic compound that is a potent inhibitor of protein kinase C and is isolated from Nocardiopsis sp K-252a SF 2370: indolocarbazole isolated from Actinomadura sp. SF-2370; structure given in first source | bridged compound; gamma-lactam; methyl ester; organic heterooctacyclic compound | antimicrobial agent; bacterial metabolite; EC 2.7.11.13 (protein kinase C) inhibitor; tropomyosin-related kinase B receptor antagonist |
| sb 218078 | indolocarbazole | ||
| 7-butyl-6-(4-methoxyphenyl)-5H-pyrrolo[2,3-b]pyrazine | pyrroles | ||
| alvocidib | alvocidib : A synthetic dihydroxyflavone that is 5,7-dihydroxyflavone which is substituted by a 3-hydroxy-1-methylpiperidin-4-yl group at position 8 and by a chlorine at the 2' position (the (-)-3S,4R stereoisomer). A cyclin-dependent kinase 9 (CDK9) inhibitor, it has been studied for the treatment of acute myeloid leukaemia, arthritis and atherosclerotic plaque formation. alvocidib: structure given in first source | dihydroxyflavone; hydroxypiperidine; monochlorobenzenes; tertiary amino compound | antineoplastic agent; antirheumatic drug; apoptosis inducer; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| aftin-4 | aftin-4: increases production of amyloid-beta protein (1-42) | ||
| su 9516 | |||
| arcyriaflavin a | arcyriaflavin A: from marine ascidian, Eudistoma sp.; structure given in first source | indolocarbazole | |
| pd 0183812 | PD 0183812: inhibits CDK4 and CDK6; structure in first source | ||
| palbociclib | aminopyridine; aromatic ketone; cyclopentanes; piperidines; pyridopyrimidine; secondary amino compound; tertiary amino compound | antineoplastic agent; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor | |
| olomoucine ii | olomoucine II: structure in first source | ||
| cyc 116 | 4-methyl-5-(2-(4-morpholinophenylamino)pyrimidin-4-yl)thiazol-2-amine: an aurora kinase inhibitor; structure in first source | ||
| 2-[[6-[(phenylmethyl)amino]-9-propan-2-yl-2-purinyl]amino]ethanol | thiopurine | ||
| cvt 313 | CVT 313: a potent inhibitor of CDK2 that prevents neointimal proliferation; structure given in first source | ||
| ((3z)-n-(3-chlorophenyl)-3-((3,5-dimethyl-4-((4-methylpiperazin-1-yl)carbonyl)-1h-pyrrol-2-yl)methylene)-n-methyl-2-oxo-2,3-dihydro-1h-indole-5-sulfonamide) | sulfonamide | ||
| azd2858 | aromatic amine; N-methylpiperazine; pyrazines; pyridines; secondary carboxamide; sulfonamide | antineoplastic agent; bone density conservation agent; EC 2.7.11.26 (tau-protein kinase) inhibitor; Wnt signalling activator | |
| nu 6140 | 4-(6-cyclohexylmethoxy-9H-purin-2-ylamino)-N,N-diethylbenzamide: a cyclin-dependent kinase inhibitor; structure in first source | ||
| rgb 286638 | |||
| at 7519 | 4-(2,6-dichlorobenzamido)-N-(piperidin-4-yl)-pyrazole-3-carboxamide : A member of the class of pryrazoles that is 4-amino-1H-pyrazole-3-carboxylic acid in which the primary amino group has been acylated by a 2,6-dichlorobenzoyl group and in which the carboxylic acid has been converted into a carboxamide by formal condensation with the primary amino group of 4-aminopiperidine. | dichlorobenzene; piperidines; pyrazoles; secondary carboxamide | antineoplastic agent; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| pha 848125 | N,1,4,4-tetramethyl-8-((4-(4-methylpiperazin-1-yl)phenyl)amino)-4,5-dihydro-1H-pyrazolo(4,3-h)quinazoline-3-carboxamide: a cyclin dependent kinase inhibitor | ||
| 14-methyl-20-oxa-5,7,14,26-tetraazatetracyclo(19.3.1.1(2,6).1(8,12))heptacosa-1(25),2(26),3,5,8(27),9,11,16,21,23-decaene | 14-methyl-20-oxa-5,7,14,26-tetraazatetracyclo(19.3.1.1(2,6).1(8,12))heptacosa-1(25),2(26),3,5,8(27),9,11,16,21,23-decaene: has antineoplastic activity; also inhibits Fms-like tyrosine kinase-3; structure in first source | ||
| azd5438 | sulfonamide | ||
| p276-00 | P276-00: antineoplastic, cyclin-dependent kinase inhibitor; structure in first source | ||
| cx 4945 | |||
| bms 754807 | BMS 754807: an IGR-1R kinase inhibitor; structure in first source | pyrazoles; pyridines; pyrrolidines; pyrrolotriazine | antineoplastic agent; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor |
| pci 32765 | ibrutinib : A member of the class of acrylamides that is (3R)-3-[4-amino-3-(4-phenoxyphenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine in which the piperidine nitrogen is replaced by an acryloyl group. A selective and covalent inhibitor of the enzyme Bruton's tyrosine kinase, it is used for treatment of B-cell malignancies. ibrutinib: a Btk protein inhibitor | acrylamides; aromatic amine; aromatic ether; N-acylpiperidine; pyrazolopyrimidine; tertiary carboxamide | antineoplastic agent; EC 2.7.10.2 (non-specific protein-tyrosine kinase) inhibitor |
| cink4 | CINK4: cyclin-dependent kinase 4 inhibitor; may have tumor suppression activity; structure in first source | indoles | |
| bs 194 | |||
| (R)-DRF053 | (R)-DRF053 : A member of the class of 2,6-diaminopurines that is 2,6-diamiopurine which is substituted by an isopropyl group at position 9 and in which the amino groups at positions 2 and 6 are substituted by a 1-hydroxybutan-2-yl and 3-(pyridin-2-yl)phenyl groups, respectively (the R enantiomer). A cyclin dependent kinase inhibitor, widely used as its hydrochloride hydrate. | 2,6-diaminopurines; phenylpyridine; primary alcohol; secondary amino compound | EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| ribociclib | ribociclib: inhibits both CDK4 and CDK6 | ||
| bay 1000394 | roniciclib: an antineoplastic agent that inhibits cyclin-dependent kinases; structure in first source | ||
| pha 793887 | piperidinecarboxamide | ||
| abemaciclib | |||
| dinaciclib | pyrazolopyrimidine | ||
| nms p937 | NMS P937: a polo-like kinase 1 inhibitor; structure in first source | ||
| gilteritinib | gilteritinib : A member of the class of pyrazines that is pyrazine-2-carboxamide which is substituted by {3-methoxy-4-[4-(4-methylpiperazin-1-yl)piperidin-1-yl]phenyl}nitrilo, (oxan-4-yl)nitrilo and ethyl groups at positions 3,5 and 6, respectively. It is a potent inhibitor of FLT3 and AXL tyrosine kinase receptors (IC50 = 0.29 nM and 0.73 nM, respectively). Approved by the FDA for the treatment of acute myeloid leukemia in patients who have a FLT3 gene mutation. gilteritinib: an FLT3/AXL protein tyrosine kinase inhibitor | aromatic amine; monomethoxybenzene; N-methylpiperazine; oxanes; piperidines; primary carboxamide; pyrazines; secondary amino compound | antineoplastic agent; apoptosis inducer; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor |
| bs-181 | BS-181: a CDK7 inhibitor with antineoplastic activity | pyrazolopyrimidine | |
| butyrolactone i | butyrolactone I: selective inhibitor of cdk2 & cdc2 kinase; structure given in first source | butenolide | |
| on123300 | ON123300: a protein kinase inhibitor; structure in first source | ||
| GS-443902 | GS-441524 triphosphate: intracellular active metabolite of remdesivir GS-443902 : An organic triphosphate that is GS-441524 in which the 5'-hydroxy group has been replaced by a triphosphate group. It is the active metabolite of remdesivir. | aromatic amine; C-nucleoside; nitrile; organic triphosphate; pyrrolotriazine | anticoronaviral agent; antiviral drug; drug metabolite |
| can 508 | CAN 508: has antiangiogenic activity; structure in first source CAN-508 : A member of the class of pyrazoles that is 1H-pyrazole substituted by amino, (4-hydroxyphenyl)diazenyl, and amino groups at positions 3, 4 and 5, respectively. It is a CDK9 inhibitor (IC50 = 0.35 muM) with 38-fold selectivity for CDK9/cyclin T over other CDK/cyclin complexes. | aromatic amine; monoazo compound; phenols; pyrazoles | angiogenesis inhibitor; antineoplastic agent; apoptosis inducer; EC 2.7.11.22 (cyclin-dependent kinase) inhibitor |
| ro 3306 | RO 3306: structure in first source | ||
| hymenialdisine | |||
| n(2)-(4-n-butylphenyl) 2'-deoxyguanosine | N(2)-(4-n-butylphenyl) 2'-deoxyguanosine: RN & structure given in first source |