{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T22:08:14Z","timestamp":1787004494000,"version":"build-2736575974"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1988,11,15]]},"abstract":"<jats:p>Previous work has led to the identification of a novel class of effector molecules [DIFs (differentiation-inducing factors) 1-3] released from the slime mould Dictyostelium discoideum. These substances induce stalk-cell differentiation in Dictyostelium discoideum and are thought to act as morphogens in the generation of the prestalk\/prespore pattern during development. The DIFs are phenylalkan-1-ones, with chloro, hydroxy and methoxy substitution on the benzene ring. DIFs 1-3 and a number of their analogues have been synthesized by using a simple two-step procedure, and each analogue has been characterized by m.s., u.v. and n.m.r. spectroscopy. The crystal structure of synthetic DIF-1 [1-(3,5-dichloro-2,6-dihydroxy-4-methoxyphenyl)hexan-1-one, was investigated. The specific biological activity of each analogue was determined in a bioassay, where isolated Dictyostelium amoebae are induced to differentiate into stalk cells. The major biologically active substance, DIF-1, caused 50% stalk-cell differentiation at 1.8 x 10(-10) M; the C4 alkyl homologue (DIF-2) and C6 homologue possessed 40 and 16% of the activity of DIF-1 respectively. Further increase or decrease in the alkyl chain length resulted in a marked decrease in specific activity. The pattern of substitution on the benzene ring is a major determinant of bioactivity, since the specific activities of the 2,4-dihydroxy-6-methoxy and trihydroxy analogues were less than 1% of that of DIF-1. Substitution of bromine in DIF-1 had little effect on bioactivity; in contrast the activity of monochloro-DIF-1 (DIF-3) was diminished. There was no evidence for antagonism or synergy between DIF-1 and any of its analogues. This series of analogues will facilitate further studies in the biological effects and mode of action of DIF-1.<\/jats:p>","DOI":"10.1042\/bj2560023","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T17:12:39Z","timestamp":1439226759000},"page":"23-28","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":71,"title":["Differentiation-inducing factor from the slime mould\n                    <i>Dictyostelium discoideum<\/i>\n                    and its analogues. Synthesis, structure and biological activity"],"prefix":"10.1042","volume":"256","author":[{"given":"M S","family":"Masento","sequence":"first","affiliation":[{"name":"Department of Biochemistry, Imperial College of Science and Technology, London SW7 2AZ, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H R","family":"Morris","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Imperial College of Science and Technology, London SW7 2AZ, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G W","family":"Taylor","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacology, Royal Postgraduate Medical School, London W12 OHS, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S J","family":"Johnson","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Imperial College of Science and Technology, London SW7 2AY, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A C","family":"Skapski","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Imperial College of Science and Technology, London SW7 2AY, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R R","family":"Kay","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/256\/1\/23\/594662\/bj2560023.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/256\/1\/23\/594662\/bj2560023.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,25]],"date-time":"2021-11-25T14:13:07Z","timestamp":1637849587000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/256\/1\/23\/36572\/Differentiation-inducing-factor-from-the-slime"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1988,11,15]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1988,11,15]]}},"URL":"https:\/\/doi.org\/10.1042\/bj2560023","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1988,11,15]]}}}