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71.
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Hiroshi Abe Takeshi Shimoda Jun Ohnishi Soichi Kugimiya Mari Narusaka Shigemi Seo Yoshihiro Narusaka Shinya Tsuda Masatomo Kobayashi 《BMC plant biology》2009,9(1):97
Background
The western flower thrips (Frankliniella occidentalis [Pergande]) is one of the most important insect herbivores of cultivated plants. However, no pesticide provides complete control of this species, and insecticide resistance has emerged around the world. We previously reported the important role of jasmonate (JA) in the plant's immediate response to thrips feeding by using an Arabidopsis leaf disc system. In this study, as the first step toward practical use of JA in thrips control, we analyzed the effect of JA-regulated Arabidopsis defense at the whole plant level on thrips behavior and life cycle at the population level over an extended period. We also studied the effectiveness of JA-regulated plant defense on thrips damage in Chinese cabbage (Brassica rapa subsp. pekinensis). 相似文献74.
Morita T Kumakura N Morishima K Mitsuboshi T Ishida M Hara T Kudo S Miwa M Ihara S Higuchi K Takeuchi Y Yoshizaki G 《Biology of reproduction》2012,86(6):176
Although the yellowtail (Seriola quinqueradiata) is the fish most commonly farmed in Japan, breeding of this species has not yet started. This is primarily due to the lack of sufficiently sophisticated methods for manipulating gametogenesis, which makes it difficult to collect gametes from specific dams and sires. If it were possible to produce large numbers of surrogate fish by transplanting germ cells isolated from donor individuals harboring desirable genetic traits, then the probability of acquiring gametes carrying the donor-derived haplotype would increase, and breeding programs involving this species might increase as a result. As a first step, we established a method for the allogeneic transplantation of yellowtail spermatogonia and the production of donor-derived offspring. Donor cells were collected from immature (10-month-old) yellowtail males with testes containing abundant type A spermatogonia, labeled with PKH26 fluorescent dye, and transferred into the peritoneal cavities of 8-day-old larvae. Fluorescence observation at 28 days post-transplantation revealed that PKH26-labeled cells were incorporated into recipients' gonads. To assess whether donor-derived spermatogonia could differentiate into functional gametes in the allogeneic recipient gonads, gametes collected from nine male and four female adult recipients were fertilized with wild-type eggs and milt. Analysis of microsatellite DNA markers confirmed that some of the first filial (F(1)) offspring were derived from donor fish, with the average contribution of donor-derived F(1) offspring being 66% and the maximum reaching 99%. These findings confirmed that our method was effective for transplanting yellowtail spermatogonia into allogeneic larvae to produce donor-derived offspring. 相似文献
75.
Toru Terachi 《Journal of plant research》1993,106(1):75-79
Recent advances in manipulating nucleic acids have opened a new research field called plant molecular systematics. This short
review provides an overview of molecular techniques which have been used in the analysis of DNA molecules for the study of
plant systematics, with a special emphasis on PCR. The early application of DNA analysis, DNA/DNA hybridization, has not become
popular with plant systematists, because of several disadvantages inherent in the method. The survey of restriction fragment
length polymorphisms (RFLPs), on the contrary, has become one of the preferred methods used by plant molecular systematists,
since the method is relatively easy to perform. Although unambiguous data can be obtained by both long-range restriction mapping
and nucleotide sequencing, these approaches may have limited use in plant molecular systematics because of their laborious
experimental procedures relying on conventional molecular cloning techniques. To date, PCR based analyses of the DNA molecule
seem to be the most suitable experimental approach for plant molecular systematics. Several advantages of the method have
changed both the quality and quantity of the DNA data. Further application of PCR to plant molecular systematics will open
up a new era in the field.
The present paper is based on the contribution which was read in a symposium entitled “Organellar DNA Variations in Higher
Plants and their Taxonomic Significance”, at the 50th Annual Meeting of the Botanical Society of Japan in Shizuoka on October
2, 1990, under the auspices of the Japan Society of Plant Taxonomists. 相似文献
76.
Go Suzuki Wataru Okada Yoko Yasutake Hidekazu Yamamoto Iwao Tanita Hiroshi Yamashita Takeshi Hayashibara Toshiaki Komatsu Toru Kanyama Masahito Inoue Masashi Yamazaki 《Restoration Ecology》2020,28(5):1172-1182
Larval recruitment is essential for sustaining coral communities and a fundamental tool in some interventions for reef restoration. To improve larval supply and post‐settlement survival in sexually assisted coral restoration efforts, an integrated in situ collector system, the larval cradle, was designed to collect spawned gametes then culture the resulting larvae until settled on artificial substrates. The final design of the larval cradle was cylindrical, a nylon mesh structure with a volume of 9 m3, suspended in the sea and extending vertically toward the seabed. We found three key design features that improved the efficiency of the apparatus: (1) an open area of sea surface and mesh size of less than 100 μm produced high fertilization and optimal survival (>90%), (2) a special skirt‐shaped net (3 m in diameter) with a connection hose for attaching the cradle to collect bundles from many adult colonies over a wide area and at various depths, and (3) adding short square tube pieces, called square hollow sections, as a substrate for enhancing larval settlement and survival, to a larval cradle at 4 days after spawning was optimal for uniform settlement. This system allowed not only the collection of several million eggs, but also subsequent production of several thousand settled juvenile corals, without land facilities. Our design achieved several hundred times higher survival for early life stages of Acropora tenuis compared to nature. 相似文献
77.
78.
Sense-overlapping lncRNA as a decoy of translational repressor protein for dimorphic gene expression
Christelle Alexa Garcia Perez Shungo Adachi Quang Dang Nong Nikko Adhitama Tomoaki Matsuura Toru Natsume Tadashi Wada Yasuhiko Kato Hajime Watanabe 《PLoS genetics》2021,17(7)
Long noncoding RNAs (lncRNAs) are vastly transcribed and extensively studied but lncRNAs overlapping with the sense orientation of mRNA have been poorly studied. We analyzed the lncRNA DAPALR overlapping with the 5´ UTR of the Doublesex1 (Dsx1), the male determining gene in Daphnia magna. By affinity purification, we identified an RNA binding protein, Shep as a DAPALR binding protein. Shep also binds to Dsx1 5´ UTR by recognizing the overlapping sequence and suppresses translation of the mRNA. In vitro and in vivo analyses indicated that DAPALR increased Dsx1 translation efficiency by sequestration of Shep. This regulation was impaired when the Shep binding site in DAPALR was deleted. These results suggest that Shep suppresses the unintentional translation of Dsx1 by setting a threshold; and when the sense lncRNA DAPALR is expressed, DAPALR cancels the suppression caused by Shep. This mechanism may be important to show dimorphic gene expressions such as sex determination and it may account for the binary expression in various developmental processes. 相似文献
79.
Potyviruses are one of the most destructive viral pathogens of Solanaceae plants. In Capsicum annuum landrace CM334, a broad-spectrum gene, Pvr4 is known to be involved in resistance against multiple potyviruses, including Pepper mottle virus (PepMoV), Pepper severe mosaic virus (PepSMV), and Potato virus Y (PVY). However, a potyvirus avirulence factor against Pvr4 has not been identified. To identify the avirulence factor corresponding to Pvr4 in potyviruses, we performed Agrobacterium-mediated transient expressions of potyvirus protein coding regions in potyvirus-resistant (Pvr4) and -susceptible (pvr4) pepper plants. Hypersensitive response (HR) was observed only when a RNA-dependent RNA polymerase (NIb) of PepMoV, PepSMV, or PVY was expressed in Pvr4-bearing pepper leaves in a genotype-specific manner. In contrast, HR was not observed when the NIb of Tobacco etch virus (TEV), a virulent potyvirus, was expressed in Pvr4-bearing pepper leaves. Our results clearly demonstrate that NIbs of PepMoV, PepSMV, and PVY serve as avirulence factors for Pvr4 in pepper plants. 相似文献
80.
Michiya Sugimori Yumiko Hayakawa Bruce M. Boman Jeremy Z. Fields Miharu Awaji Hiroko Kozano Ryoi Tamura Seiji Yamamoto Toru Ogata Mitsuhiko Yamada Shunro Endo Masanori Kurimoto Satoshi Kuroda 《PloS one》2015,10(8)