59456-70-1 WWJFFVUVFNBJTN-UIBIZFFUSA-N WWJFFVUVFNBJTN-UIBIZFFUSA-N Nikkomycins β-D-Allofuranuronic acid, 5-[[(2S,3S,4S)-2-amino-4-hydroxy-4-(5-hydroxy-2-pyridinyl)-3-methyl-1-oxobutyl]amino]-1,5-dideoxy-1-(3,4-dihydro-2,4-dioxo-1(2H)-pyrimidinyl)- DTXSID5058436 CHEBI:17029 CHEBI chitin GO:0006031 GO chitin biosynthetic process D009026 MESH mortality 1 WIKI increased Polyoxin D 2020-10-23T06:20:12 2020-10-23T06:20:12 Nikkomycins 2018-05-24T15:54:09 2018-05-24T15:54:09 7375 NCBI Lucilia cuprina WCS_35525 common ecological species Daphnia magna Decrease, 20-hydroxyecdysone Molecular AOPWiki 2022-08-28T21:14:06 2022-08-28T21:14:06 Decrease, knickkopf gene Cellular AOPWiki 2022-08-28T21:15:01 2022-08-28T21:15:01 Decrease, Chitin laminar organization Tissue AOPWiki 2022-08-28T21:16:27 2022-08-28T21:16:27 Decrease, Prevent chitin degradation by chitinases Tissue AOPWiki 2022-08-28T21:17:28 2022-08-28T21:17:28 Weak, Procuticle protection Organ AOPWiki 2022-08-28T21:18:06 2022-08-28T21:18:06 Decrease, New cuticle secretion Organ AOPWiki 2022-08-28T21:18:54 2022-08-28T21:18:54 Increase, Incomplete ecdysis Individual AOPWiki 2016-11-29T18:41:28 2018-05-24T16:41:34 Increase, developmental abnormalities Individual AOPWiki 2022-08-28T20:41:02 2022-08-28T20:41:02 Increase, Mortality Individual <p><span style="font-size:14px">This key event is observed at the biological level of the individual and describes the increase of mortality of individuals upon exposure to a stressor.</span></p> <p><span style="font-size:14px">The AO can be detected by observation, for example by immobilization of the respective organisms. There exist guidelines for the characterization of this AO in arthropods. For example, the OECD 202 Daphnia sp. Acute immobilization test&nbsp;</span><!--[if supportFields]><span lang=EN-US style='font-size:11.0pt;line-height:107%;font-family:"Calibri",sans-serif; mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font: minor-latin;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;mso-ansi-language:EN-US;mso-fareast-language: EN-US;mso-bidi-language:AR-SA'><span style='mso-element:field-begin;mso-field-lock: yes'></span>ADDIN CSL_CITATION {&quot;citationItems&quot;:[{&quot;id&quot;:&quot;ITEM-1&quot;,&quot;itemData&quot;:{&quot;DOI&quot;:&quot;10.1787/9789264069947-en&quot;,&quot;ISBN&quot;:&quot;9789264069947&quot;,&quot;PMID&quot;:&quot;128&quot;,&quot;abstract&quot;:&quot;This Test Guideline describes an acute toxicity test to assess effects of chemicals towards daphnids (usually Daphnia magna Staus). Young daphnids, aged less than 24 hours at the start of the test, are exposed to the test substance at a range of concentrations (at least five concentrations) for a period of 48 hours. Immobilisation is recorded at 24 hours and 48 hours and compared with control values. The results are analysed in order to calculate the EC50 at 48h. Determination of the EC50 at 24h is optional. At least 20 animals, preferably divided into four groups of five animals each, should be used at each test concentration and for the controls. At least 2 ml of test solution should be provided for each animal (i.e. a volume of 10 ml for five daphnids per test vessel). The limit test corresponds to one dose level of 100 mg/L. The study report should include the observation for immobilized daphnids at 24 and 48 hours after the beginning of the test and the measures of dissolved oxygen, pH, concentration of the test substance, at the beginning and end of the test.&quot;,&quot;author&quot;:[{&quot;dropping-particle&quot;:&quot;&quot;,&quot;family&quot;:&quot;OECD&quot;,&quot;given&quot;:&quot;&quot;,&quot;non-dropping-particle&quot;:&quot;&quot;,&quot;parse-names&quot;:false,&quot;suffix&quot;:&quot;&quot;}],&quot;collection-title&quot;:&quot;OECD Guidelines for the Testing of Chemicals, Section 2&quot;,&quot;container-title&quot;:&quot;OECD Publishing&quot;,&quot;id&quot;:&quot;ITEM-1&quot;,&quot;issue&quot;:&quot;OECD Guideline for the Testing of Chemicals, Section 2&quot;,&quot;issued&quot;:{&quot;date-parts&quot;:[[&quot;2004&quot;,&quot;11&quot;,&quot;23&quot;]]},&quot;number-of-pages&quot;:&quot;1-12&quot;,&quot;publisher&quot;:&quot;OECD&quot;,&quot;title&quot;:&quot;Test No. 202: &lt;i&gt;Daphnia sp.&lt;/i&gt; Acute Immobilisation Test&quot;,&quot;type&quot;:&quot;report&quot;},&quot;uris&quot;:[&quot;http://www.mendeley.com/documents/?uuid=53ebeac3-a1c9-3977-9697-df1efabeb4d3&quot;]}],&quot;mendeley&quot;:{&quot;formattedCitation&quot;:&quot;(OECD 2004)&quot;,&quot;plainTextFormattedCitation&quot;:&quot;(OECD 2004)&quot;},&quot;properties&quot;:{&quot;noteIndex&quot;:0},&quot;schema&quot;:&quot;https://github.com/citation-style-language/schema/raw/master/csl-citation.json&quot;}<span style='mso-element:field-separator'></span></span><![endif]-->(OECD 2004)<!--[if supportFields]><span lang=EN-US style='font-size:11.0pt;line-height:107%;font-family:"Calibri",sans-serif; mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font: minor-latin;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;mso-ansi-language:EN-US;mso-fareast-language: EN-US;mso-bidi-language:AR-SA'><span style='mso-element:field-end'></span></span><![endif]--><span style="font-size:14px"> which can also be modified depending on the effect one expects.</span></p> <p><span style="font-size:14px"><strong>Taxonomic: </strong>This AO is applicable to all living organisms.</span></p> <p><span style="font-size:14px"><strong>Life stage: </strong>This AO&nbsp;is applicable to all life stages.</span></p> <p><span style="font-size:14px"><strong>Sex: </strong>This AO is applicable to all sexes.</span></p> <p><span style="font-size:14px"><strong>Chemical:</strong> Substances known to increase mortality in arthropods are of the family of pyrimidine nucleosides (e.g. polyoxin D and nikkomycin Z) (Gijswijt et al. 1979; Tellam et al. 2000; Arakawa et al. 2008).</span></p> High Unspecific High All life stages High High <p><span style="font-size:14px">Arakawa T, Yukuhiro F, Noda H. 2008. Insecticidal effect of a fungicide containing polyoxin B on the larvae of <em>Bombyx mori</em> (Lepidoptera: Bombycidae), <em>Mamestra brassicae</em>, <em>Mythimna separata</em>, and <em>Spodoptera litura</em> (Lepidoptera: Noctuidae). Appl Entomol Zool. 43(2):173&ndash;181. doi:10.1303/aez.2008.173.</span></p> <p><span style="font-size:14px">Gijswijt MJ, Deul DH, de Jong BJ. 1979. Inhibition of chitin synthesis by benzoyl-phenylurea insecticides, III. Similarity in action in <em>Pieris brassicae</em> (L.) with Polyoxin D. Pestic Biochem Physiol. 12(1):87&ndash;94. doi:10.1016/0048-3575(79)90098-1.</span></p> <p><span style="font-size:14px">OECD. 2004. Test No. 202: <em>Daphnia sp.</em> Acute Immobilisation Test. OECD OECD Guidelines for the Testing of Chemicals, Section 2. [accessed 2020 Mar 3]. https://www.oecd-ilibrary.org/environment/test-no-202-daphnia-sp-acute-immobilisation-test_9789264069947-en.</span></p> <p><span style="font-size:14px">Tellam RL, Vuocolo T, Johnson SE, Jarmey J, Pearson RD. 2000. Insect chitin synthase. cDNA sequence, gene organization and expression. Eur J Biochem. 267(19):6025&ndash;6043. doi:10.1046/j.1432-1327.2000.01679.x.</span></p> AOPWiki 2016-11-29T18:41:24 2020-10-26T05:18:16 AOPWiki 2022-08-28T21:21:31 2022-08-28T21:21:31 AOPWiki 2022-08-28T21:21:48 2022-08-28T21:21:48 AOPWiki 2022-08-28T21:22:02 2022-08-28T21:22:02 AOPWiki 2022-08-28T21:22:23 2022-08-28T21:22:23 AOPWiki 2022-08-28T21:22:37 2022-08-28T21:22:37 AOPWiki 2022-08-28T21:23:05 2022-08-28T21:23:05 AOPWiki 2022-08-28T21:23:20 2022-08-28T21:23:20 AOPWiki 2022-08-28T21:23:38 2022-08-28T21:23:38 AOPWiki 2022-08-28T20:44:25 2022-08-28T20:44:25 Knickkopf leading to mortality Agnes Aggy <p>Donggon Yoo^1,2 , Ihn-Sil Kwak^3,4, Woo-Keun Kim^1,2*</p> <p>&nbsp;</p> <p>&nbsp;</p> <p>1.&nbsp;Human and Environmental Toxicology, University of Science and Technology, Daejeon, 34113, Korea</p> <p>2.&nbsp;Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114, Korea</p> <p>3.&nbsp;Fisheries Science Institute, Chonnam National University, Yeosu, 59626, Korea</p> <p>4. Faculty of Marine Technology, Chonnam National University, Yeosu, 59626, Korea</p> BY-SA 2.5 <p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-family:&quot;Arial&quot;,sans-serif">On the basis of the literature, we propose the AOP associated with the molting process. During growth, insects must undergo a process of molting along with the development of their cuticles, in which old cuticles are replaced with new ones. Chitinase present in the molting fluid breaks down chitin in old cuticles, providing a substrate for the synthesis of new cuticles. The presence of the chitin-binding protein Knickkopf (Knk) in a new procuticle under development has been shown to be important for protecting chitin from degradation by active chitinase. Knockout and repression of the KnK gene result in chitinase-dependent degradation of chitin in new cuticles, molt defects, developmental arrest, and mortality.</span></span></span></p> <p><span style="font-size:11.0pt"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:black">This process affects chitin laminar organization and is prevented by chitinases. This results in the weakening of procuticle protection and a decrease in of new cuticle secretion. And it induces an incomplete moulting process, which causes malformations and increases the mortality rate of immature individuals</span></span></span></p> <p><span style="font-size:11.0pt"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:black">Based on a literature review, we proposed the conceptual AOP framework associated with Knickkopf, leading to mortality. Based on the paper, the molecular mechanism of Knickkopf&#39;s molting is relatively clear. However, the supporting information on Knickkopf and related KEs is not sufficient yet. We believe our animal model experiment data and further gene analysis can validate the key regulators in the suggested AOP. Then, we can suggest essentiality and evidence for each KEs based on animal model studies. The process for this AOP validation needs at least one year. This AOP is related to the molting process and it is thought that it will be helpful for research use together with the existing AOP (4, 358~361).</span></span></span></p> adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate adjacent Moderate Moderate <div> <table class="table table-bordered table-fullwidth"> <thead> <tr> <th>Modulating Factor (MF)</th> <th>Influence or Outcome</th> <th>KER(s) involved</th> </tr> </thead> <tbody> <tr> <td>&nbsp;</td> <td>&nbsp;</td> <td>&nbsp;</td> </tr> </tbody> </table> </div> AOPWiki 2022-08-28T21:06:53 2024-05-26T20:39:58