2,361 research outputs found
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Letter to Irene Crespin from H.B. Stenzel on 1962-05-22
No full textJackson School of Geoscience
Type B Phosphatidylinositol-4-Phosphate 5-Kinases Mediate Arabidopsis and Nicotiana tabacum Pollen Tube Growth by Regulating Apical Pectin Secretion
No full textPhosphatidylinositol-4,5-bisphosphate [PtdIns(4,5)P(2)] occurs in the apical plasma membrane of growing pollen tubes. Because enzymes responsible for PtdIns(4,5) P(2) production at that location are uncharacterized, functions of PtdIns( 4,5) P(2) in pollen tube tip growth are unresolved. Two candidate genes encoding pollen-expressed Arabidopsis thaliana phosphatidylinositol-4-phosphate 5-kinases (PI4P 5-kinases) of Arabidopsis subfamily B were identified (PIP5K4 and PIP5K5), and their recombinant proteins were characterized as being PI4P 5-kinases. Pollen of T-DNA insertion lines deficient in both PIP5K4 and PIP5K5 exhibited reduced pollen germination and defects in pollen tube elongation. Fluorescence-tagged PIP5K4 and PIP5K5 localized to an apical plasma membrane microdomain in Arabidopsis and tobacco (Nicotiana tabacum) pollen tubes, and overexpression of either PIP5K4 or PIP5K5 triggered multiple tip branching events. Further studies using the tobacco system revealed that overexpression caused massive apical pectin deposition accompanied by plasma membrane invaginations. By contrast, callose deposition and cytoskeletal structures were unaltered in the overexpressors. Morphological effects depended on PtdIns(4,5) P(2) production, as an inactive enzyme variant did not produce any effects. The data indicate that excessive PtdIns(4,5) P2 production by type B PI4P 5-kinases disturbs the balance of membrane trafficking and apical pectin deposition. Polar tip growth of pollen tubes may thus be modulated by PtdIns(4,5) P(2) via regulatory effects on membrane trafficking and/or apical pectin deposition.German Research Foundatio
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Letter to Irene Crespin from H.B. Stenzel on 1964-02-03
No full textJackson School of Geoscience
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Letter to Irene Crespin from H.B. Stenzel on 1963-04-03
No full textJackson School of Geoscience
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Letter to Irene Crespin from H.B. Stenzel on 1961-01-24
No full textJackson School of Geoscience
Letter from Yosh and Irene [Kuromiya] to Michi Weglyn
No full textA letter from Yosh and Irene [Kuromiya] asking Michi Weglyn for materials to create "a pictorial history of the life of Michi Nishiura Weglyn photos and documents" for the tribute to Michi Weglyn on February 21, 1998.These materials are from box 73 and 74 of the Frank Chin Papers. The Frank Chin Papers contain personal and professional correspondence between Frank Chin and Michi Weglyn relating to particular projects on which either author was working as well as files related to the Day of Remembrance Tribute to Michi Weglyn
The Mindful Christian with Irene Kraegel
No full textOur guest for this episode is Irene Kraegel, the author of The Mindful Christian. We examine how Christian life is enhanced by mindfulness
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Letter to H.B. Stenzel from Irene Crespin on Undated
No full textJackson School of Geoscience
Hydroxylated jasmonates are commonly occurring metabolites of jasmonic acid and contribute to a partial switch‐off in jasmonate signaling
No full textIn potato 12-hydroxyjasmonic acid (12-OH-JA) is a tuber-inducing compound. Here, it is demonstrated that 12-OH-JA, as well as its sulfated and glucosylated derivatives, are constituents of various organs of many plant species. All accumulate differentially and usually to much higher concentrations than jasmonic acid (JA). In wounded tomato leaves, 12-OH-JA and its sulfated, as well as glucosylated, derivative accumulate after JA, and their diminished accumulation in wounded leaves of the JA-deficient mutants spr2 and acx1 and also a JA-deficient 35S::AOCantisense line suggest their JA-dependent formation. To elucidate how signaling properties of JA/JAME (jasmonic acid methyl ester) are affected by hydroxylation and sulfation, germination and root growth were recorded in the presence of the different jasmonates, indicating that 12-OH-JA and 12-hydroxyjasmonic acid sulfate (12-HSO4-JA) were not bioactive. Expression analyses for 29 genes showed that expression of wound-inducible genes such as those coding for PROTEINASE INHIBITOR2, POLYPHENOL OXIDASE, THREONINE DEAMINASE or ARGINASE was induced by JAME and less induced or even down-regulated by 12-OH-JA and 12-HSO4-JA. Almost all genes coding for enzymes in JA biosynthesis were up-regulated by JAME but down-regulated by 12-OH-JA and 12-HSO4-JA. The data suggest that wound-induced metabolic conversion of JA/JAME into 12-OH-JA alters expression pattern of genes including a switch off in JA signaling for a subset of genes
Ein Intellektueller zwischen Kaiserreich und Exil
No full textDas Werk des eigenwilligen Philosophen und Gesellschaftskritikers Constantin Brunner (1862–1937) hat in den letzten Jahren eine vermehrte Aufmerksamkeit vor allem in der Kulturgeschichte gefunden. Die in diesem Band versammelten interdisziplinären Beiträge analysieren Brunners oft provokante Thesen und ihre vielfältigen Wirkungen in zeitgenössischen philosophischen und kulturgeschichtlichen Kontexten des Kaiserreichs, der Weimarer Republik und des Exils. Brunners Literatur-, Wissenschafts- und Religionskritik gehört zu den vieldiskutierten Stimmen seiner Zeit. In den Beiträgen des Bandes werden seine Analyse des Antisemitismus und Nationalismus sowie seine scharfe Kritik am Zionismus ebenso untersucht wie sein Einfluss auf Persönlichkeiten wie Gustav Landauer, Martin Buber, Lou Andreas-Salomé und Walther Rathenau. Aufgeschlüsselt werden Brunners biographische Kontexte und der große Kreis von Freunden und Verehrern, die Brunner als eine intellektuelle Leitfigur geschätzt haben
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