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1. Combined Pre-Supernova Alert System with Kamland and Super-Kamiokande

Author

KamLAND, Collaborations, Super-Kamiokande, Abe, Seisho, Eizuka, Minori, Futagi, Sawako, Gando, Azusa, Gando, Yoshihito, Goto, Shun, Hachiya, Takahiko, Hata, Kazumi, Ichimura, Koichi, Ieki, Sei, Ikeda, Haruo, Inoue, Kunio, Ishidoshiro, Koji, Kamei, Yuto, Kawada, Nanami, Kishimoto, Yasuhiro, Koga, Masayuki, Kurasawa, Maho, Mitsui, Tadao, Miyake, Haruhiko, Morita, Daisuke, Nakahata, Takeshi, Nakajima, Rika, Nakamura, Kengo, Nakamura, Rikuo, Nakamura, Ryo, Nakane, Jun, Ozaki, Hideyoshi, Saito, Keita, Sakai, Taichi, Shimizu, Itaru, Shirai, Junpei, Shiraishi, Kensuke, Shoji, Ryunosuke, Suzuki, Atsuto, Takeuchi, Atsuto, Tamae, Kyoko, Watanabe, Hiroko, Watanabe, Kazuho, Yoshida, Sei, Umehara, Saori, Fushimi, Ken-Ichi, Kotera, Kenta, Urano, Yusuke, Berger, Bruce E., Fujikawa, Brian K., Larned, John G., Maricic, Jelena, Fu, Zhenghao, Smolsky, Joseph, Winslow, Lindley A., Efremenko, Yuri, Karwowski, Hugon J., Markoff, Diane M., Tornow, Werner, Dell'Oro, Stefano, O'Donnell, Thomas, Detwiler, Jason A., Enomoto, Sanshiro, Decowski, Michal P., Weerman, Kelly M., Grant, Christopher, Song, Hasung, Li, Aobo, Axani, Spencer N., Garcia, Miles, Abe, Ko, Bronner, Christophe, Hayato, Yoshinari, Hiraide, Katsuki, Hosokawa, Keishi, Ieki, Kei, Ikeda, Motoyasu, Kameda, June, Kanemura, Yuki, Kaneshima, Ryota, Kashiwagi, Yuri, Kataoka, Yousuke, Miki, Shintaro, Mine, Shunichi, Miura, Makoto, Moriyama, Shigetaka, Nakahata, Masayuki, Nakano, Yuuki, Nakayama, Shoei, Noguchi, Yohei, Sato, Kazufumi, Sekiya, Hiroyuki, Shiba, Hayato, Shimizu, Kotaro, Shiozawa, Masato, Sonoda, Yutaro, Suzuki, Yoichiro, Takeda, Atsushi, Takemoto, Yasuhiro, Tanaka, Hidekazu K., Yano, Takatomi, Han, Seungho, Kajita, Takaaki, Okumura, Kimihiro, Tashiro, Takuya, Tomiya, Takuya, Wang, Xubin, Yoshida, Shunsuke, Fernandez, Pablo, Labarga, Luis, Ospina, Nataly, Zaldivar, Bryan, Pointon, Barry W., Kearns, Edward, Raaf, Jennifer L., Wan, Linyan, Wester, Thomas, Bian, Jianming, Griskevich, Jeff, Smy, Michael B., Sobel, Henry W., Takhistov, Volodymyr, Yankelevich, Alejandro, Hill, James, Jang, MinCheol, Lee, Seonghak, Moon, DongHo, Park, RyeongGyoon, Bodur, Baran, Scholberg, Kate, Walter, Chris W., Beauchêne, Antoine, Drapier, Olivier, Giampaolo, Alberto, Mueller, Thomas A., Santos, Andrew D., Paganini, Pascal, Quilain, Benjamin, Rogly, Rudolph, Nakamura, Taku, Jang, Jee-Seung, Machado, Lucas N., Learned, John G., Choi, Koun, Iovine, Nadege, Cao, Son V., Anthony, Lauren H. V., Martin, Daniel G. R., Prouse, Nick W., Scott, Mark, Uchida, Yoshi, Berardi, Vincenzo, Calabria, Nicola F., Catanesi, M. G., Radicioni, Emilio, Langella, Aurora, de Rosa, Gianfranca, Collazuol, Gianmaria, Feltre, Matteo, Iacob, Fabio, Mattiazzi, Marco, Ludovici, Lucio, Gonin, Michel, Périssé, Lorenzo, Pronost, Guillaume, Fujisawa, Chiori, Horiuchi, Shogo, Kobayashi, Misaki, Liu, Yu-Ming, Maekawa, Yuto, Nishimura, Yasuhiro, Okazaki, Reo, Akutsu, Ryosuke, Friend, Megan, Hasegawa, Takuya, Ishida, Taku, Kobayashi, Takashi, Jakkapu, Mahesh, Matsubara, Tsunayuki, Nakadaira, Takeshi, Nakamura, Kenzo, Oyama, Yuichi, Sakashita, Ken, Sekiguchi, Tetsuro, Tsukamoto, Toshifumi, Yrey, Antoniosk Portocarrero, Bhuiyan, Nahid, Burton, George T., Di Lodovico, Francesca, Gao, Joanna, Goldsack, Alexander, Katori, Teppei, Migenda, Jost, Ramsden, Rory M., Xie, Zhenxiong, Zsoldos, Stephane, Suzuki, Atsumu T., Takagi, Yusuke, Takeuchi, Yasuo, Zhong, Haiwen, Feng, Jiahui, Feng, Li-Cheng, Hu, Jianrun, Hu, Zhuojun, Kawaue, Masaki, Kikawa, Tatsuya, Mori, Masamitsu, Nakaya, Tsuyoshi, Wendell, Roger A., Yasutome, Kenji, Jenkins, Sam J., McCauley, Neil K., Mehta, Pruthvi, Tarrant, Adam, Wilking, Mike J., Fukuda, Yoshiyuki, Itow, Yoshitaka, Menjo, Hiroaki, Ninomiya, Kotaro, Yoshioka, Yushi, Lagoda, Justyna, Mandal, Maitrayee, Mijakowski, Piotr, Prabhu, Yashwanth S., Zalipska, Joanna, Jia, Mo, Jiang, Junjie, Shi, Wei, Yanagisawa, Chiaki, Harada, Masayuki, Hino, Yota, Ishino, Hirokazu, Koshio, Yusuke, Nakanishi, Fumi, Sakai, Seiya, Tada, Tomoaki, Tano, Tomohiro, Ishizuka, Takeharu, Barr, Giles, Barrow, Daniel, Cook, Laurence, Samani, Soniya, Wark, David, Holin, Anna, Nova, Federico, Jung, Seunghyun, Yang, Byeongsu, Yang, JeongYeol, Yoo, Jonghee, Fannon, Jack E. P., Kneale, Liz, Malek, Matthew, McElwee, Jordan M., Thiesse, Matthew D., Thompson, Lee F., Wilson, Stephen T., Okazawa, Hiroko, Mohan, Lakshmi S., Kim, SooBong, Kwon, Eunhyang, Seo, Ji-Woong, Yu, Intae, Ichikawa, Atsuko K., Nakamura, Kiseki D., Tairafune, Seidai, Nishijima, Kyoshi, Eguchi, Aoi, Nakagiri, Kota, Nakajima, Yasuhiro, Shima, Shizuka, Taniuchi, Natsumi, Watanabe, Eiichiro, Yokoyama, Masashi, de Perio, Patrick, Fujita, Saki, Jesus-Valls, Cesar, Martens, Kai, Tsui, Ka M., Vagins, Mark R., Xia, Junjie, Izumiyama, Shota, Kuze, Masahiro, Matsumoto, Ryo, Terada, Kotaro, Asaka, Ryusei, Ishitsuka, Masaki, Ito, Hiroshi, Ommura, Yuga, Shigeta, Natsuki, Shinoki, Masataka, Yamauchi, Koki, Yoshida, Tsukasa, Gaur, Rhea, Gousy-Leblan, Vincent, Hartz, Mark, Konaka, Akira, Li, Xiaoyue, Chen, Shaomin, Xu, Benda, Zhang, Aiqiang, Zhang, Bin, Posiadala-Zezula, Magdalena, Boyd, Steven B., Edwards, Rory, Hadley, David, Nicholson, Matthew, O'Flaherty, Marcus, Richards, Benjamin, Ali, Ajmi, Jamieson, Blair, Amanai, Shogo, Marti-Magro, Lluis, Minamino, Akihiro, Shibayama, Ryo, and Suzuki, Serina

Subjects
High Energy Physics - Experiment, Astrophysics - High Energy Astrophysical Phenomena, Physics - Instrumentation and Detectors
Abstract

Preceding a core-collapse supernova, various processes produce an increasing amount of neutrinos of all flavors characterized by mounting energies from the interior of massive stars. Among them, the electron antineutrinos are potentially detectable by terrestrial neutrino experiments such as KamLAND and Super-Kamiokande via inverse beta decay interactions. Once these pre-supernova neutrinos are observed, an early warning of the upcoming core-collapse supernova can be provided. In light of this, KamLAND and Super-Kamiokande, both located in the Kamioka mine in Japan, have been monitoring pre-supernova neutrinos since 2015 and 2021, respectively. Recently, we performed a joint study between KamLAND and Super-Kamiokande on pre-supernova neutrino detection. A pre-supernova alert system combining the KamLAND detector and the Super-Kamiokande detector was developed and put into operation, which can provide a supernova alert to the astrophysics community. Fully leveraging the complementary properties of these two detectors, the combined alert is expected to resolve a pre-supernova neutrino signal from a 15 M$_{\odot}$ star within 510 pc of the Earth, at a significance level corresponding to a false alarm rate of no more than 1 per century. For a Betelgeuse-like model with optimistic parameters, it can provide early warnings up to 12 hours in advance., Comment: Resubmitted to ApJ. 22 pages, 16 figures, for more information about the combined pre-supernova alert system, see https://www.lowbg.org/presnalarm/

Published
2024
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2. Status and Perspectives of Neutrino Physics

Author

Athar, M. Sajjad, Barwick, Steven W., Brunner, Thomas, Cao, Jun, Danilov, Mikhail, Inoue, Kunio, Kajita, Takaaki, Kowalski, Marek, Lindner, Manfred, Long, Kenneth R., Palanque-Delabrouille, Nathalie, Rodejohann, Werner, Schellman, Heidi, Scholberg, Kate, Seo, Seon-Hee, Smith, Nigel J. T., Winter, Walter, Zeller, Geralyn P., and Funchal, Renata Zukanovich

Subjects
High Energy Physics - Phenomenology, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Nuclear Experiment
Abstract

This review demonstrates the unique role of the neutrino by discussing in detail the physics of and with neutrinos. We deal with neutrino sources, neutrino oscillations, absolute masses, interactions, the possible existence of sterile neutrinos, and theoretical implications. In addition, synergies of neutrino physics with other research fields are found, and requirements to continue successful neutrino physics in the future, in terms of technological developments and adequate infrastructures, are stressed., Comment: 227 pages; this review of the field of neutrino physics emerged from a report written by a panel on the request of IUPAP (International Union of Pure and Applied Physics). The mandate, the panel members and the report can be found on the web page of the panel at ht tps://www.iupapneutrinopanel.org

Published
2021
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3. Geoneutrinos and geoscience: an intriguing joint-venture

Author

Bellini, Gianpaolo, Inoue, Kunio, Mantovani, Fabio, Serafini, Andrea, Strati, Virginia, and Watanabe, Hiroko

Subjects
Physics - Geophysics, High Energy Physics - Experiment
Abstract

The review is conceived to help the reader to interpret present geoneutrino results in the framework of Earth's energetics and composition. Starting from the comprehension of antineutrino production, propagation, and detection, the status of the geoneutrino field is presented through the description of the experimental and technological features of the Borexino and KamLAND ongoing experiments. The current understanding of the energetical, geophysical and geochemical traits of our planet is examined in a critical analysis of the currently available models. By combining theoretical models and experimental results, the mantle geoneutrino signal extracted from the results of the two experiments demonstrates the effectiveness in investigating deep earth radioactivity through geoneutrinos from different sites. The obtained results are discussed and framed in the puzzle of the diverse classes of formulated Bulk Silicate Earth models, analyzing their implications on planetary heat budget and composition. As a final remark, we present the engaging technological challenges and the future experiments envisaged for the next decade in the geoneutrino field., Comment: Submitted to "La Rivista del Nuovo Cimento"

Published
2021
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4. High purity NaI(Tl) scintillator to search for dark matter

Author

Fushimi, Ken-Ichi, Ejiri, Hiroyasu, Hazama, Ryuta, Ikeda, Haruo, Inoue, Kunio, Imagawa, Kyoshiro, Kanzaki, Gakuji, Kozlov, Alexandre, Orito, Reiko, Shima, Tatsushi, Takemoto, Yasuhiro, Teraoka, Yuri, Umehara, Saori, and Yoshida, Sei

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

A high purity and large volume NaI(Tl) scintillator was developed to search for cosmic dark matter. The required densities of radioactive impurities (RIs) such as U-chain, Th-chain are less than a few ppt to establish high sensitivity to dark matter. The impurity of RIs were effectively reduced by selecting raw materials of crucible and by performing chemical reduction of lead ion in NaI raw powder. The impurity of $^{226}$Ra was reduced less than 100 $\mu$Bq/kg in NaI(Tl) crystal. It should be remarked that the impurity of $^{210}$Pb, which is difficult to reduce, is effectively reduced by chemical processing of NaI raw powder down to less than 30 $\mu$Bq/kg. The expected sensitivity to cosmic dark matter by using 250 kg of the high purity and large volume NaI(Tl) scintillator (PICO-LON; Pure Inorganic Crystal Observatory for LOw-background Neutr(al)ino) is 7$\times$10$^{-45}$ cm$^{2}$ for 50 GeV$/c^{2}$ WIMPs., Comment: 6 pages, 2 Figures, Proceedings of International Symposium on Radiation Detectors and Their Uses (ISRD2016). Talk given on 19th Jan. 2016 by K.Fushimi. To be published in Proceedings will be published as JPS conference proceedings (2016)

Published
2016
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7. Neutrino Physics around MeV Energies

Author

Inoue, Kunio and Minakata, Hisakazu

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

We present a brief informative overview of a broad ranges of subjects, the solar, the reactor, the geo and the supernova neutrinos (but without excluding possible biases), the topics which consist of the session ``Neutrino Physics around MeV Energies'' in NOW2006. Contrary to the naive expectation, the field is found to be very active in improving the performance of existing detectors, and in preparation for the development coming in the near future. The former includes excellent performance of SNO 3He detector, successful reconstruction of SK III, and KamLAND's new ``4pi'' calibration. The next data release from these experiments will be very exciting. The latter includes effort for lowering threshold in SK III, KamLAND's purification by which geo-neutrino observation becomes much cleaner, and the forthcoming 7Be neutrino measurement by BOREXINO and KamLAND. Possible detection of relic supernova neutrinos and non-zero effect of theta_{13} would bring us great excitement. Furthermore, improved new measurement of heavy element abundance in the solar atmosphere resulted in a solar model with much lower CNO \nu flux and with disagreement with helioseismology, thereby bringing us a new solar puzzle., Comment: 6 pages, 2 figures, Conveners' report for NOW2006 Proceedings

Published
2006
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23. The germ cell‐specific TAP‐like protein NXF‐2 forms a novel granular structure and is required for tra‐2 3′UTR‐dependent mRNA export in Caenorhabditis elegans.

Author

Miwa, Takashi, Ohtani, Keigo, Inoue, Kunio, and Sakamoto, Hiroshi

Subjects
MESSENGER RNA, CAENORHABDITIS elegans, RNA regulation, CAENORHABDITIS, GERM cells, GENE expression, PROTEINS, MEIOSIS
Abstract

TAP is a general mRNA export receptor and is highly conserved among eukaryotes. The nematode Caenorhabditis elegans has another TAP‐like protein, NXF‐2, but little is known about its function. In this study, we show that NXF‐2 is specifically expressed in germ cells and forms a novel granular structure that is different from that of P granules and that NXF‐2 granules are anchored to the nuclear periphery in the mitotic region of the hermaphrodite gonad. In contrast, NXF‐2 granules are released within the whole cytoplasm in the meiotic region, where the feminization gene tra‐2 starts to function. Both inhibition of XPO‐1 (an ortholog of the export receptor CRM1) and mutation of the nuclear export signal of NXF‐2 caused the release of NXF‐2 granules from the nuclear periphery, indicating that anchoring of NXF‐2 granules depends on XPO‐1 function. Moreover, inhibition of NXF‐2 resulted in a substantial nuclear accumulation of the reporter mRNA carrying the tra‐2 3′UTR. These results suggest that, together with XPO‐1, NXF‐2 exports and anchors tra‐2 mRNA to the nuclear periphery to avoid precocious translation until the germ cells reach the meiotic region, thereby contributing to the regulation of tra‐2 mRNA expression. [ABSTRACT FROM AUTHOR]

Published
2022
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24. Simulation study of Ocean Bottom Detector(OBD) for observation of geo-neutrinos from the mantle

Author

Sakurai, Noriaki, Eiichirou Araki, Kyo, Masanori, Mcdonough, William, Inoue, Kunio, Yoshida, Hiroshi, Watanabe, Hiroko, Kasaya, Takafumi, Ueki, Kenta, Sakai, Taichi, and Natsue Abe

Subjects
Physics::Instrumentation and Detectors, High Energy Physics::Experiment, Physics::Geophysics
Abstract

By the observation of geo-neutrinos originating from radioactive isotopes in the Earth (238U,232Th), we can know the amount of radioactive isotopes and the radiogenic heat which governs the Earth dynamics. Ocean Bottom Detector can observe geo-neutrinos from the mantle directly. Unlike existing other neutrino detectors, OBD detects neutrinos on the seafloor. Given that the oceanic crust is thinner than the continental crust and has lower densities of U and Th, ~70% of anti-neutrinos at OBD come from the mantle. Another unique feature of OBD is keeping the distance from the reactors which are the main background sources for continental detectors. In addition, this movable detector can observe at multiple points in the ocean. Currently we are considering the detector design. I estimated backgrounds from structures of detector and set upper limit of amount of isotopes. We will present results of detector design based on MC simulation.

Published
2020
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27. Localized maternal factors are required for zebrafish germ cell formation

Author

Hashimoto, Yoshiko, Maegawa, Shingo, Nagai, Terumi, Yamaha, Etsuro, Suzuki, Hitoshi, Yasuda, Kunio, and Inoue, Kunio

Subjects
Zebra fish -- Research, Biological sciences
Abstract

Maternally supplied factors in fertilized eggs play essential roles in the establishment of primordial germ cells. In zebrafish, cytoplasm at the distal ends of the first and second cleavage furrows has been assumed to contain germ lineage determinants, since maternal transcripts of germ lineage-specific genes are localized to ends of the cleavage furrows. To investigate whether these parts of cytoplasm are required for germ cell formation, we removed all four regions of the cytoplasm by glass capillary at the 4-cell stage. Histological analysis revealed that the ablation of cytoplasm at the ends of the cleavage planes resulted in a severe reduction in the number of germ cells. In addition, the expression of germ lineage markers was eliminated by cytoplasmic ablation. These results demonstrated that cytoplasm at the distal ends of cleavage furrows is essential for germ cell formation. We also found novel localization patterns for zDazl and brul mRNAs along the cleavage planes. Our findings provide the first direct evidence that localized cytoplasmic factors are indispensable for germ cell establishment in zebrafish. Keywords: Zebrafish; Primordial gem cell (PGC); Germ plasm; vasa; nanos1; Maternal cytoplasmic components; mRNA localization; zDazl; brul

Published
2004

30. A Distinct Subset of Human Short Introns: U2AF Heterodimer Is Replaced by SPF45 (RBM17) as General Splicing Factor

Author

Fukumura, Kazuhiro, Yoshimoto, Rei, Hirose, Tetsuro, Inoue, Kunio, and Mayeda, Akila

Abstract

SUMMARY Human pre-mRNA introns vary in size from under fifty to over a million nucleotides. We searched for specific splicing factors involved in human short introns by screening siRNAs against 154 human nuclear proteins for activity on a model short 56-nucleotide intron-containing HNRNPH1 pre-mRNA. We identified a known alternative splicing regulator SPF45 (RBM17) as a general splicing factor that is essential to splice out this 56-nt intron. Whole-transcriptome sequencing of SPF45 deficient cells revealed that SPF45 is specifically required for the efficient splicing of many short introns. Our crosslinking and biochemical analyses demonstrate that SPF45 specifically replaces U2AF heterodimer on the truncated pyrimidine tracts. To initiate splicing, the U2AF-homology motif (UHM) of the replaced SPF45 interacts with the UHM-ligand motif (ULM) of the U2 snRNP protein SF3b155 (SF3b1). We propose the existence of a distinct subset of SPF45-dependently spliced short introns.

Published
2019
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35. PICOLON dark matter search ˜ Development of highly redio-pure NaI(Tl) scintilltor ˜

Author

Fushimi, Ken-Ichi, primary, Chernyak, Dmitry, additional, Ejiri, Hiroyasu, additional, Hata, Kazumi, additional, Hazama, Ryuta, additional, Hirata, Shoko, additional, Iida, Takashi, additional, Ikeda, Haruo, additional, Inoue, Kunio, additional, Imagawa, Kyoshiro, additional, Kanemitsu, Yuta, additional, Kozlov, Alexandle, additional, Orito, Reiko, additional, Shima, Tatsushi, additional, Takemoto, Yasuhiro, additional, Umehara, Saori, additional, and Yoshida, Sei, additional

Published
2020
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39. A useful approach to total analysis of RISC-associated RNA

Author

Inoue Kunio, Nishibu Takahiro, Hayashida Yukinobu, and Kurokawa Tsutomu

Subjects
Medicine, Biology (General), QH301-705.5, Science (General), Q1-390
Abstract

Abstract Background Identifying the endogenous RNA induced silencing complex(RISC)-associated RNAs is essential for understanding the cellular regulatory networks by miRNAs. Recently, isolation of RISC-associated mRNAs using antibody was reported, but their method needs a large amount of initial materials. We tried to improve the protocol and constructed an efficient and convenient system for analyzing miRNA and mRNA contents in RISC. Findings With our protocol, it is possible to clone both miRNAs and mRNAs from the endogenous RISC-associated RNAs immunoprecipitated from less than 107 cells, and we show the ability of our system to isolate the particular target mRNAs for a specific miRNA from the RISC-associated mRNAs using well-characterized miR-122 as an example. After introduction of miR-122 into HepG2 cells, we found several cDNA clones that have miR-122 target sequences. Four of these clones that were concentrated in RISC but decreased in total RNA fraction are expected to be miR-122 target candidates. Interestingly, we found substantial amounts of Alu-related sequences, including both free Alu RNA and Alu-embedded mRNA, which might be one of the general targets for miRNA, in the cDNA clones from the RISC-associated mRNAs. Conclusion Our method thus enables us to examine not only dynamic changes in miRNA and mRNA contents in RISC but also the relationship of miRNA and target mRNA. We believe that our method can contribute to understanding cellular regulatory networks by miRNAs.

Published
2009
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42. Binding of the Drosophila sex-lethal gene product to the alternative splice site of transformer primary transcript

Author

Inoue, Kunio, Hoshijima, Kazuyuki, Sakamoto, Hiroshi, and Shimura, Yoshiro

Subjects
Fruit-flies -- Genetic aspects, Genetic transformation -- Physiological aspects, Genetic transcription -- Laws, regulations and rules, Antisense DNA -- Physiological aspects, Messenger RNA -- Physiological aspects, Drosophila -- Genetic aspects, Environmental issues, Science and technology, Zoology and wildlife conservation
Published
1990

43. MRG‐1 is required for both chromatin‐based transcriptional silencing and genomic integrity of primordial germ cells in Caenorhabditis elegans.

Author

Miwa, Takashi, Inoue, Kunio, and Sakamoto, Hiroshi

Subjects
*CAENORHABDITIS elegans, *GERM cells, *RNA polymerase II, *CHROMOSOME structure, *SILENCE, *INTEGRITY
Abstract

In Caenorhabditis elegans, germline cells remain transcriptionally silenced during embryogenesis. The transcriptional silencing is achieved by two different mechanisms: One is the inhibition of RNA polymerase II in P2‐P4 cells at the establishment stage, and another is chromatin‐based silencing in two primordial germ cells (PGCs) at the maintenance stage; however, the molecular mechanism underlying chromatin‐based silencing is less understood. We investigated the role of the chromodomain protein MRG‐1, which is an essential maternal factor for germline development, in transcriptional silencing in PGCs. PGCs lacking maternal MRG‐1 showed increased levels of two histone modifications (H3K4me2 and H4K16ac), which are epigenetic markers for active transcription, and precocious activation of germline promoters. Loss of MES‐4, a H3K36 methyltransferase, also caused similar derepression of the germline genes in PGCs, suggesting that both MRG‐1 and MES‐4 function in chromatin‐based silencing in PGCs. In addition, the mrg‐1 null mutant showed abnormal chromosome structures and a decrease in homologous recombinase RAD‐51 foci in PGCs, but the mes‐4 null mutant did not show such phenotypes. Taken together, we propose that MRG‐1 has two distinct functions: chromatin‐based transcriptional silencing and preserving genomic integrity at the maintenance stage of PGCs. [ABSTRACT FROM AUTHOR]

Published
2019
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44. Germ-line chimera produced by blastoderm transplantation in zebrafish

Author

Nagai, Terumi, Otani, Satoshi, Saito, Taiju, Maegawa, Shingo, Inoue, Kunio, Arai, Katsutoshi, and Yamaha, Etsuro

Subjects
生殖系列キメラ, ゼブラフィッシュ, PGCs, 胚盤移植, 始原生殖細胞
Abstract

To elucidate the effects of blastoderm graft for chimeric-fish production on further development, transplantations of upper, lower or entire part of blastoderm were performed onto the animal part of host embryos during the blastula stage in zebrafish. In the case of upper, all resultant chimeric embryos developed normally, while in the lower part, many acephalic embryos appeared. When the entire blastoderm was transplanted, many resultant embryos showed normal phenotype with extra cell-mass, while a few had double axis. vas mRNA, one of the markers of PGCs, also kept the expressions in both donor and recipient blastomeres in transplantation of the entire blastoderm. Donor PGCs were frequently detected at germinal anlagen in histological sections of 6-day larvae developed from transplantations of lower and entire blastoderm, but seldom in those of the upper part. These results might suggest that graft transplantation was effective for production of germ-line chimera, but sometimes caused un-regulaory differentiation of graft cells under the community effect.

Published
2005

45. The Germ Cell Lineage Identified by vas-mRNA during the Embryogenesis in Goldfish

Author

Otani, Satoshi, Maegawa, Shingo, Inoue, Kunio, Arai, Katsutoshi, and Yamaha, Etsuro

Subjects
primordial germ cell, PGCs, vas, goldfish, zebrafish
Abstract

vas RNA has been identified in germ-line cells and its precursors in zebrafish, with the result that the germ-line lineage can be traced throughout embryogenesis. In the present study, we described vas localization and the migration of vas-positive cells in goldfish, using whole mount in situ hybridization. The signals of vas mRNA localization appeared at the marginal part of the first to third cleavage planes. The eight signals were detected during the period from the 8- cells to the 512-cell stage. At the late-blastula stage, additional numbers of vas-positive cells were observed, suggesting the proliferation of these cells. At the segmentation period, vas-positive cells showed a long extended distribution along the embryonic axis, but did not form any clusters. vas-positive cells were occasionally distributed at the head region, especially around the future otic vesicle. These signals were inherited to the primordial germ cells, suggesting that vas-positive cells were primordial germ cells (PGCs) in goldfish.

Published
2002

46. The exon junction complex controls the efficient and faithful splicing of a subset of transcripts involved in mitotic cell-cycle progression

Author

Fukumura, Kazuhiro, Wakabayashi, Shunichi, Kataoka, Naoyuki, Sakamoto, Hiroshi, Suzuki, Yutaka, Nakai, Kenta, Mayeda, Akila, Inoue, Kunio, Fukumura, Kazuhiro, Wakabayashi, Shunichi, Kataoka, Naoyuki, Sakamoto, Hiroshi, Suzuki, Yutaka, Nakai, Kenta, Mayeda, Akila, and Inoue, Kunio

Abstract

The exon junction complex (EJC) that is deposited onto spliced mRNAs upstream of exon–exon junctions plays important roles in multiple post-splicing gene expression events, such as mRNA export, surveillance, localization, and translation. However, a direct role for the human EJC in pre-mRNA splicing has not been fully understood. Using HeLa cells, we depleted one of the EJC core components, Y14, and the resulting transcriptome was analyzed by deep sequencing (RNA-Seq) and confirmed by RT–PCR. We found that Y14 is required for efficient and faithful splicing of a group of transcripts that is enriched in short intron-containing genes involved in mitotic cell-cycle progression. Tethering of EJC core components (Y14, eIF4AIII or MAGOH) to a model reporter pre-mRNA harboring a short intron showed that these core components are prerequisites for the splicing activation. Taken together, we conclude that the EJC core assembled on pre-mRNA is critical for efficient and faithful splicing of a specific subset of short introns in mitotic cell cycle-related genes.

Published
2016

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