Taxonomic study on the order Kickxellales (Zygomycetes, Zygomycota)

筑波大学University of Tsukuba博士（理学）Doctor of Philosophy in ScienceThe order Kickxellales is a relatively small fungal group that belongs to the class Zygomycetes of the phylum Zygomycota. The members of the order are mainly saprobes and inhabit in soil or dung of herbivorous or omnivoroud mammals, and only a few species are ...2002Includes bibliographical referencesdoctoral thesi

Distinctive development of embryo and endosperm caused by male gametes irradiated with carbon-ion beam

Pollen irradiation with ionizing radiations has been applied in plant breeding and genetic research, and haploid plant induction has mainly been performed by male inactivation with high-dose irradiation. However, the fertilization process of irradiated male gametes and the early development of embryo and endosperm have not received much attention. Heavy-ion beams, a type of radiation, have been widely applied as effective mutagens for plants and show a high mutation rate even at low-dose irradiation. In this study, we analyzed the effects of male gametes of Cyrtanthus mackenii irradiated with a carbon-ion beam at low doses on fertilization. In immature seeds derived from the pollination of irradiated pollen grains, two types of embryo sacs were observed: embryo sac with a normally developed embryo and endosperm and embryo sac with an egg cell or an undivided zygote and an endosperm. Abnormalities in chromosome segregation, such as chromosomal bridges, were observed only in the endosperm nuclei, irrespective of the presence or absence of embryogenesis. Therefore, in Cyrtanthus, embryogenesis is strongly affected by DNA damage or mutations in male gametes. Moreover, various DNA contents were detected in the embryo and endosperm nuclei, and endoreduplication may have occurred in the endosperm nuclei. As carbon-ion irradiation causes chromosomal rearrangements even at low doses, pollen irradiation can be an interesting tool for studying double fertilization and mutation heritability.Citation: Hirano, T., Murata, M., Watarikawa, Y. et al. Distinctive development of embryo and endosperm caused by male gametes irradiated with carbon-ion beam. Plant Reprod (2024). https://doi.org/10.1007/s00497-024-00496-

Measurement of the Lifetime Difference in D0 Meson Decays

journal articl

一九世紀初頭東北農村の肝入日記 －「文化2年 乙丑日記」

departmental bulletin pape

Presentation_1_Evidence for the Involvement of Fatty Acid Biosynthesis and Degradation in the Formation of Insect Sex Pheromone-Mimicking Chiloglottones in Sexually Deceptive Chiloglottis Orchids.PDF

<p>Hundreds of orchid species secure pollination by sexually luring specific male insects as pollinators by chemical and morphological mimicry. Yet, the biochemical pathways involved in the synthesis of the insect sex pheromone-mimicking volatiles in these sexually deceptive plants remain poorly understood. Here, we explore the biochemical pathways linked to the chemical mimicry of female sex pheromones (chiloglottones) employed by the Australian sexually deceptive Chiloglottis orchids to lure their male pollinator. By strategically exploiting the transcriptomes of chiloglottone 1-producing Chiloglottis trapeziformis at distinct floral tissues and at key floral developmental stages, we identified two key transcriptional trends linked to the stage- and tissue-dependent distribution profiles of chiloglottone in the flower: (i) developmental upregulation of fatty acid biosynthesis and β-oxidation genes such as KETOACYL-ACP SYNTHASE, FATTY ACYL-ACP THIOESTERASE, and ACYL-COA OXIDASE during the transition from young to mature buds and flowers and (ii) the tissue-specific induction of fatty acid pathway genes in the callus (the insectiform odor-producing structure on the labellum of the flower) compared to the labellum remains (non-odor-producing) regardless of development stage of the flower. Enzyme inhibition experiments targeting KETOACYL-ACP SYNTHASE activity alone in three chiloglottone-producing species (C. trapeziformis, C. valida, and C. aff. valida) significantly inhibited chiloglottone biosynthesis up to 88.4% compared to the controls. These findings highlight the role of coordinated (developmental stage- and tissue-dependent) fatty acid gene expression and enzyme activities for chiloglottone production in Chiloglottis orchids.</p

Ratios of lycosantalene levels to β-phellandrene and β-caryophyllene levels in petiolule with and without trichomes, and in trichomes of transgenic <i>S</i>. <i>lycopersicum</i> plants overexpressing <i>CPT2</i>.

<p>Terpenes were extracted with hexane and analyzed by GC-MA as described in Materials and Methods.</p><p>Ratios of lycosantalene levels to β-phellandrene and β-caryophyllene levels in petiolule with and without trichomes, and in trichomes of transgenic <i>S</i>. <i>lycopersicum</i> plants overexpressing <i>CPT2</i>.</p

NNPS activity of CPT2.

<p>NNPS activity of CPT2.</p

qRT-PCR analyses of <i>CPT2</i>, <i>TPS21</i> and <i>CYP71BN1</i> transcripts in different tissues of <i>S</i>. <i>lycopersicum</i>.

<p>Total RNA was isolated from various tomato tissues. Leaflets and petiolules were prepared from four different developmental compound leaf stages. Error bars represent SE. Values are from three biological and three technical replicates.</p

Phylogenetic tree of tomato CYP71BN1 and other functionally characterized terpene-modifying P450s.

<p>Neighbor-joining phylogenetic tree analysis using amino acid sequences was performed by MEGA 5 [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119302#pone.0119302.ref040" target="_blank">40</a>]. Bootstrap values were performed with 1000 replications (values shown next to branches). LsGAO1, <i>Lactuca sativa</i> germacrene A oxidase (GAO) 1 (ADF32078.1); CiGAO2, <i>Cichorium intybus</i> (ADF43080.1); HaGAO4, <i>Helianthus annuus</i> (ADF43082.1); ScGAO3, <i>Saussurea costus</i> (ADF43081.1); AaAMO1, <i>Artemisia annua</i> amorpha-4, 11-diene monooxygenase (Q1PS23.1); BsGAO5, <i>Barnadesia spinosa</i> (ADF43083.1); HmHPO, <i>Hyoscyamus muticus</i> premnaspirodiene oxygenase (HPO) (A6YIH8.1); Nt-CYP71D20, <i>Nicotiana tabacum</i> 5-epiaristolochene dihydroxylase (Q94FM7.2); Ms-CYP71D18, <i>Mentha spicata</i> (-)-(4<i>S</i>)-limonene-6-hydroxylase (Q9XHE8.1); Mp-CYP71D13, <i>Mentha x piperita</i> (-)-(4<i>S</i>)-limonene-3-hydroxylase (Q9XHE7.1); Mp-CYP71D15, <i>Mentha x piperita</i> (-)-(4<i>S</i>)-limonene-3-hydroxylase (Q9XHE6.1); Zz-CYP71BA1, <i>Zingiber zerumbet</i> α-humulene oxidase (E3W9C4.1); AtKO, <i>Arabidopsis thaliana ent</i>-kaurene oxidase (KO) (NM_122491); OsKO2, <i>Oryza sativa</i> (BAF19823); OsKO4, <i>Oryza sativa</i> (BAF19823).</p

Lycosantalonol biosynthesis in <i>Solanum lycopersicum</i>.

<p>(<b>A</b>) The terpene gene cluster on the tip of chromosome 8. (<b>B</b>) The biosynthetic pathway to lycosantanolol. AOX, alcohol oxidase; TPS, terpene synthase; CPT, <i>cis</i>-prenyl transferase; NDPS1, neryl diphosphate synthase 1; CYP, cytochrome P450; AAT, alcohol acyltransferase; DMAPP, dimethylallyl diphosphate; IPP, isopentenyl diphosphate; NNPP, nerylneryl diphosphate. Genes that are not functional because of deletions or insertions are shown with a “ψ” symbol.</p