著者

Tomohiro Araki Jiro Osaka Yuya Kato Mai Shimozono Hinata Kawamura Riku Iwanaga Satoko Hakeda-Suzuki Takashi Suzuki

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.19-00066, (Released:2020-06-04)

参考文献数

25

被引用文献数

4

---

In many animals, neural activity contributes to the adaptive refinement of synaptic properties, such as firing frequency and the number of synapses, for learning, memorizing and adapting for survival. However, the molecular mechanisms underlying such activity-dependent synaptic remodeling remain largely unknown. In the synapses of Drosophila melanogaster, the presynaptic active zone (AZ) forms a T-shaped presynaptic density comprising AZ proteins, including Bruchpilot (Brp). In a previous study, we found that the signal from a fusion protein molecular marker consisting of Brp and mCherry becomes diffuse under continuous light over three days (LL), reflecting disassembly of the AZ, while remaining punctate under continuous darkness. To identify the molecular players controlling this synaptic remodeling, we used the fusion protein molecular marker and performed RNAi screening against 208 neuron-related transmembrane genes that are highly expressed in the Drosophila visual system. Second analyses using the STaR (synaptic tagging with recombination) technique, which showed a decrease in synapse number under the LL condition, and subsequent mutant and overexpression analysis confirmed that five genes are involved in the activity-dependent AZ disassembly. This work demonstrates the feasibility of identifying genes involved in activity-dependent synaptic remodeling in Drosophila, and also provides unexpected insight into the molecular mechanisms involved in cholesterol metabolism and biosynthesis of the insect molting hormone ecdysone.

著者

禹 長春

出版者

The Genetics Society of Japan

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.6, no.3, pp.205-205, 1930

著者

禹 長春

出版者

The Genetics Society of Japan

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.1, no.2, pp.101-106, 1922

著者

Kei Fukuda

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.23-00140, (Released:2023-10-20)

参考文献数

159

被引用文献数

3

---

Transposable elements (TEs) are mobile DNA sequences that can insert themselves into various locations within the genome, causing mutations that may provide advantages or disadvantages to individuals and species. The insertion of TEs can result in genetic variation that may affect a wide range of human traits including genetic disorders. Understanding the role of TEs in human biology is crucial for both evolutionary and medical research. This review discusses the involvement of TEs in human traits and disease susceptibility, as well as methods for functional analysis of TEs.

著者

Keiju Kishikawa Kenji Suetsugu Daisuke Kyogoku Kenji Ogaki Daisuke Iga Kohtaroh Shutoh Yuji Isagi Shingo Kaneko

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.94, no.2, pp.95-98, 2019-04-01 (Released:2019-04-27)

参考文献数

16

被引用文献数

5 5

---

We developed microsatellite markers to compare the genetic variation between the putatively cleistogamous Gastrodia takeshimensis (Orchidaceae) and its chasmogamous sister species G. nipponica. We expected low genetic variation in G. takeshimensis in view of its hypothesized cleistogamy. Eighteen primer pairs were developed from a G. takeshimensis genomic DNA library, and their characteristics were tested for G. takeshimensis and G. nipponica. Seven loci were polymorphic in G. nipponica, whereas all loci showed no polymorphism in G. takeshimensis. Genetic diversity was thus not detected in G. takeshimensis, and it seems to have been lost by repeated selfing in the completely closed flower. The 18 markers described here will be useful for investigating the genetic variation between a cleistogamous species and its chasmogamous sister species.

著者

Tomoyuki Furuya Yuki Kondo

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.23-00029, (Released:2023-06-16)

参考文献数

21

---

Members of a plant-specific BES/BZR transcription factor (TF) family including BRI1-EMS-SUPPRESSOR 1 (BES1) and BRASSINAZOLE-RESISTANT 1 (BZR1) regulate various developmental processes and environmental responses. Recently, we reported that BES1/BZR1 Homolog 3 (BEH3) exhibited a competitive effect toward other BES/BZR TFs. In this study, we analyzed transcriptome profiles in BEH3-overexpressing plants and compared them with those of BES1 and BZR1 double gain-of-function mutants. We identified 46 differentially expressed genes (DEGs), which were downregulated in the gain-of-function mutants of BES1 and BZR1 but upregulated upon BEH3 overexpression. In these DEGs, putative BES1 and BZR1 direct-targeted genes were highly enriched. In addition, these DEGs contained not only known brassinosteroid biosynthetic enzymes, but also some NAC TFs, which negatively regulate brassinosteroid-inactivating enzymes. Moreover, the iron sensor and the iron-deficient response-related bHLH TFs were also included. Taken together, our findings indicate that a competitive relationship between BEH3 and other BES/BZR TFs exists in various BES/BZR binding target genes.

著者

Naoki Shitsukawa Chihiro Ikari Sanae Shimada Satoshi Kitagawa Koichi Sakamoto Hiroyuki Saito Hiromichi Ryuto Nobuhisa Fukunishi Tomoko Abe Shigeo Takumi Shuhei Nasuda Koji Murai

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.82, no.2, pp.167-170, 2007 (Released:2007-05-11)

参考文献数

13

被引用文献数

88 98

---

The einkorn wheat (Triticum monococcum) mutant, maintained vegetative phase (mvp), was induced by nitrogen ion-beam treatment and was identified by its inability to transit from the vegetative to reproductive phase. In our previous study, we showed that WAP1 (wheat APETALA1) is a key gene in the regulatory pathway that controls phase transition from vegetative to reproductive growth in common wheat. WAP1 is an ortholog of the VRN1 gene that is responsible for vernalization insensitivity in einkorn wheat. The mvp mutation resulted from deletion of the VRN1 coding and promoter regions, demonstrating that WAP1/VRN1 is an indispensable gene for phase transition in wheat. Expression analysis of flowering-related genes in mvp plants indicated that wheat GIGANTIA (GI), CONSTANS (CO) and SUPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) genes either act upstream of or in a different pathway to WAP1/VRN1.

著者

Ryutaro Miyagi Yohey Terai

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.3, pp.145-153, 2013 (Released:2013-09-11)

参考文献数

76

被引用文献数

11 14

---

The amazing coloration shown by diverse cichlid fish not only fascinates aquarium keepers, but also receives great attention from biologists interested in speciation because of its recently-revealed role in their adaptive radiation in an African lake. We review the important role of coloration in the speciation and adaptive evolution of Lake Victoria cichlids, which have experienced adaptive radiation during a very short evolutionary period. Mature male cichlids display their colors during mate choice. The color of their skin reflects light, and the reflected light forms a color signal that is received by the visual system of females. The adaptive divergence of visual perceptions shapes and diverges colorations, to match the adapted visual perceptions. The divergence of visual perception and coloration indicates that the divergence of color signals causes reproductive isolation between species, and this process leads to speciation. Differences in color signals among coexisting species act to maintain reproductive isolation by preventing hybridization. Thus, the diversity of coloration has caused speciation and has maintained species diversity in Lake Victoria cichlids.

著者

Shasha Wang Yohei Koide Yuji Kishima

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.97, no.4, pp.177-184, 2022-08-01 (Released:2022-12-17)

参考文献数

31

---

The transposon Tam3 of Antirrhinum (snapdragon) has acquired properties that distinguish it from other transposons. Mobile DNA, commonly referred to as a transposable element or transposon, is considered to be synonymous with a selfish factor. That is, a transposable element increases in copy number and moves copies of itself independently of the survival of the host organism. Therefore, the host collectively regulates the transposition activities of most transposable elements in its genome by epigenetic means. However, our analyses of the structure and behavior of Tam3, as shown by the following five results, provide evidence that it does not behave in a selfish manner in relation to the host. 1) Active transposable elements normally increase the abundance of their non-autonomous elements, whereas Tam3 is known to have no non-autonomous elements, and a limited number of around 10 copies of autonomous elements present in the genome have been isolated as active copies. 2) Tam3 does not transpose at 25 ℃, which is the optimal growth temperature for Antirrhinum. Transposition of Tam3 occurs only at low temperatures of about 15 ℃, which is stressful for Antirrhinum. 3) Few strains of Antirrhinum have been found to contain genes that specifically suppress Tam3 transposition. 4) Most of the Tam3 insertions found in Antirrhinum genes do not affect the host genome, and the expression of these host genes is not completely suppressed. 5) Transcription and translation of the Tam3 transposase gene are not epigenetically regulated by the host. These five experimental results constitute evidence that Tam3 retains features that are dissimilar to those of many other transposons and that it does not behave in a selfish manner that is detrimental to the survival of the host. In this review, we consider what kinds of behavior are required if transposons are to establish a mutually beneficial relationship with their hosts, with reference to Tam3.

著者

Hidetaka Ito

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.97, no.4, pp.167, 2022-08-01 (Released:2022-12-17)

被引用文献数

1

著者

TOSIHIDE H. YOSIDA CHOJI TAYA

出版者

The Genetics Society of Japan

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.52, no.4, pp.289-299, 1977 (Released:2007-05-21)

参考文献数

46

被引用文献数

6 2

---

Semen of the black rat was inseminated artificially into the female Norway rat by routine technique. Among 20 rats, 9 showed pregnancy. Five impregnanted rats were dissected on 8 to 14 days after insemination and one to 4 embryos were found. No offspring were born in the case of the artificial insemination. In the control in which the semen of the Norway rat was inseminated artificially into the female Norway rat, pregnancies were obtained at high frequency and offspring were successfully born as in natural matings. Chromosomes of the hybrid blastocysts showed 42 chromosomes consisting of two haploid sets, one from the Norway rat and the other from the black rat.

著者

Masaki Shirai Takuya Nara Haruko Takahashi Kazuya Takayama Yuan Chen Yudai Hirose Masashi Fujii Akinori Awazu Nobuyoshi Shimoda Yutaka Kikuchi

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.21-00092, (Released:2022-06-18)

参考文献数

42

---

CpG methylation of genomic DNA is a well-known repressive epigenetic marker in eukaryotic transcription, and DNA methylation of promoter regions is correlated with gene silencing. In contrast to the promoter regions, the function of DNA methylation during transcription termination remains to be elucidated. A recent study revealed that mouse DNA methyltransferase 3a (Dnmt3a) mainly functions in de novo methylation in the promoter and gene body regions, including transcription termination sites (TTSs), during development. To investigate the relationship between DNA methylation overlapping the TTSs and transcription termination, we performed bioinformatics analysis using six pre-existing Dnmt-/- mouse cell datasets: four types of neurons (three Dnmt3a-/- and one Dnmt1-/- mutants) and two types of embryonic fibroblasts (MEFs) (Dnmt3a-/- and Dnmt3b-/- mutants). Combined analyses using methylome and transcriptome data revealed that read counts downstream of hypomethylated TTSs were increased in three types of neurons (two Dnmt3a-/- and one Dnmt1-/- mutants). Among these, an increase in chimeric transcripts downstream of the TTSs was observed in Dnmt3a-/- mature olfactory sensory neurons and Dnmt3a-/- agouti-related peptide (protein)-producing neurons, thereby indicating that read-through occurs in hypomethylated TTSs at specific gene loci in these two mutants. Conversely, in Dnmt3a-/- MEFs, we detected reductions in read counts downstream of hypomethylated TTSs. These results indicate that the hypomethylation of TTSs can both positively and negatively regulate transcription termination, dependent on Dnmt and cell types. This study is the first to identify the aberrant termination of transcription at specific gene loci with DNA hypomethylated TTSs attributable to Dnmt deficiency.

著者

Hiroshi Azuma Rhett D. Harrison Keiko Nakamura Zhi-Hui Su

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.85, no.3, pp.177-192, 2010 (Released:2010-10-27)

参考文献数

72

被引用文献数

12 14

---

The interaction between figs (Ficus, Moraceae) and fig-pollinating wasps (Chalcidoidea, Agaonidae) is one of the most specific mutualisms, and thus is a model system for studying coevolution and cospeciation. In this study we focused on figs and their associated fig-wasps found in the Ryukyu and Bonin (Ogasawara) Islands, Japan, because it has been suggested that breakdown in the specificity may occur in islands or at edge of a species’ distribution. We collected 136 samples of 15 native fig species and 95 samples of 13 associated fig-wasps from all major islands in the Ryukyu Islands, including two fig species and one fig-wasp species endemic to the Bonin Islands. We performed molecular phylogenetic analyses using plastid DNA and nuclear ITS sequences for the figs and nuclear 28S rRNA and mitochondrial COI genes for the fig-wasps to investigate the interspecific phylogenies and intraspecific variation within the mutualism. Our phylogenetic analyses using multiple samples per species show the single clade of each fig (except the Bonin endemic species) and fig-pollinating wasp species. Fig species belonging to the same subgenera formed well-supported clades in both plastid and ITS trees, except for the subgenus Urostigma. Likewise, fig wasps emerging from host fig species belonging to the same subgenera formed mostly well supported clades in both 28S and COI trees. Host specificity between the figs and fig-wasps functions strictly in these islands. There was very little sequence variation within species, and that no major geographic structure was found. The two Bonin endemic species (F. boninsimae and F. nishimurae) or their common ancestor and the associated fig-wasps (Blastophaga sp.) are apparently derived from F. erecta and its associated fig-wasps (B. nipponica), respectively, and probably migrated from the Ryukyu Islands.

著者

Michihiko Sugimoto

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.89, no.3, pp.109-120, 2014-06-01 (Released:2014-12-04)

参考文献数

98

被引用文献数

16 24

---

The proximal third of mouse chromosome 17 is known as the t-complex. The t-haplotype is a variant form of this region containing four tandem inversions compared with the wild-type t-complex, and thus recombination in heterozygotes of the t-haplotype is strongly suppressed along the entire t-complex region. Within this genetically locked t-haplotype, many mutations related to various interesting phenotypes (e.g., taillessness, transmission ratio distortion, recessive lethality) have accumulated, and many mouse geneticists have been attracted to t-haplotype research. Many recessive lethal mutations known as t-complex lethal mutations have been found, and detailed phenotypic analyses have revealed that the functions of t-lethal genes are related to important developmental events. Therefore, identification of the genes responsible for these lethal mutations may contribute to our understanding of the mechanisms of mammalian development. In this review, I introduce the phenotypes of t-lethal mutations and describe recent findings, including our results regarding the molecular identification of a t-lethal gene.

著者

Tomoya Suzuki Kanto Nishikawa Yukuto Sato Mamoru Toda

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.21-00046, (Released:2021-11-07)

参考文献数

25

被引用文献数

1

---

Species identification using molecular techniques has recently become common for various taxa. Loop-mediated isothermal amplification (LAMP) is one of the easiest and least expensive molecular identification methods. Although few studies have developed LAMP assays for amphibians, we believe that LAMP is also useful for identifying endangered amphibians. Hynobius tokyoensis and H. lichenatus occur in Honshu, Japan, and have parapatric distributions. They are similar morphologically, especially at early developmental stages, including eggs and larvae. Hynobius tokyoensis has been listed as a national endangered species in Japan since 2020, and unambiguous identification of these species is therefore important for their conservation and management. In this study, we developed a LAMP primer set for the mitochondrial cytochrome b region to detect H. tokyoensis, and we evaluated the LAMP assay using total genomic DNA from four H. tokyoensis and three H. lichenatus individuals from across most of their ranges. Our LAMP primer set could distinguish these two species. This study should help to establish LAMP assays for other endangered species and morphologically similar species.

著者

Yui Hayashi Kanako Takehira Kosuke Nozawa Takamasa Suzuki Yukari Masuta Atsushi Kato Hidetaka Ito

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.95, no.4, pp.183-190, 2020-08-01 (Released:2020-10-23)

参考文献数

46

被引用文献数

3 10

---

Most transposable elements (TEs) are tightly regulated by epigenetic mechanisms such as DNA methylation. RNA-directed DNA methylation (RdDM) is a major control mechanism of TE silencing in plants. We analyzed the transposition activity of a heat-responsive retrotransposon, ONSEN, in Arabidopsis thaliana. Transgenerational transposition was observed in RdDM pathway-deficient mutants upon heat stress. The transposition frequency was higher in the mutants of the upstream processes, but lower in the mutants of the downstream steps, of RdDM. The transposition frequency was not associated with the number of extrachromosomal ONSEN copies. Constitutive heterochromatin of interphase nuclei was dispersed upon heat stress. The degree of decondensation was higher in the RdDM mutants than in wild-type plants subjected to heat stress. We discuss the possible role of RdDM in the regulation of ONSEN transposition upon heat stress.

著者

Motoo KIMURA

出版者

The Genetics Society of Japan

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.66, no.4, pp.367-386, 1991 (Released:2006-06-10)

参考文献数

67

被引用文献数

98 172

---

In sharp contrast to the Darwinian theory of evolution by natural selection, the neutral theory claims that the overwhelming majority of evolutionary changes at the molecular level are caused by random fixation (due to random sampling drift in finite populations) of selectively neutral (i.e., selectively equivalent) mutants under continued inputs of mutations. The theory also asserts that most of the genetic variability within species at the molecular level (such as protein and DNA polymorphism) are selectively neutral or very nearly neutral and that they are maintained in the species by the balance between mutational input and random extinction. The neutral theory is based on simple assumptions, enabling us to develop mathematical theories based on population genetics to treat molecular evolution and variation in quantitative terms. The theory can be tested against actual observations. Neo-Darwinians continue to criticize the neutral theory, but evidence for it has accumulated over the last two decades. The recent outpouring of DNA sequence data has greatly strengthened the theory. In this paper, I review some recent observations that strongly support the neutral theory. They include such topics as pseudoglobin genes of the mouse, αA-crystallin genes of the blind mole rat, genes of influenza A virus and nuclear vs. mitochondrial genes of fruit flies. I also discuss such topics as the evolution of deviant coding systems in Mycoplasma, the origin of life and the unified understanding of molecular and phenotypic evolution. I conclude that since the origin of life on Earth, neutral evolutionary changes have predominated over Darwinian evolutionary changes, at least in number.

著者

市川 定夫

出版者

The Genetics Society of Japan

雑誌

JAPANESE JOURNAL OF GENETICS (ISSN:0021504X)

巻号頁・発行日

vol.66, no.4, pp.513-525, 1991

被引用文献数

19

---

Induced somatic pink mutation frequencies in the stamen hairs of Tradescantia KU 20 clone, a blue/pink heterozygote highly mutable spontaneously at lower temperature, were studied after treating with relatively small doses of Co-60 gamma rays (39 to 551 mGy or 3.9 to 55.1 rad), and were compared with those of two stable clones (non-mutable spontaneously), BNL 02 and KU 9, which are also blue/pink heterozygotes. It was found that the gamma-ray-induced mutation frequency in KU 20 clone was comparable (18.8 pink mutant events per 10(4) hair-cell divisions per Gy) to those in BNL 02 (12.2 and 21.2) and KU 9 (17.4) clones, when the spontaneous mutation frequencies of KU 20 clone were relatively low (at most about 5.7 and 2.3 times of BNL 02 and KU 9 clones, respectively). However, when the spontaneous mutation frequecies of KU 20 clone were much higher (up to about 65 and 27 times of BNL 02 and KU 9 clones, respectively), induced mutation frequency was significantly higher in KU 20 clone (58.8 pink mutant events per 10(4) hair-cell divisions per Gy) than in BNL 02 and KU 9 clones. The extent of increase in the gamma-ray-induced mutation frequency in the latter case was nevertheless very much less than the increase in the spontaneous mutation frequency, suggesting different mechanisms of initiation and repair of radiation-induced and spontaneous mutations.

著者

Yi-Deun Jung Kung Ahn Yun-Ji Kim Jin-Han Bae Ja-Rang Lee Heui-Soo Kim

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.1, pp.31-43, 2013 (Released:2013-05-14)

参考文献数

148

被引用文献数

4 5

---

Eukaryotic genomes comprise numerous retroelements that have a major impact on the structure and regulation of gene function. Retroelements are regulated by epigenetic controls, and they generate multiple miRNAs that are involved in the induction and progression of genomic instability. Elucidation of the biological roles of retroelements deserves continuous investigation to better understand their evolutionary features and implications for disease.

著者

Kazutoshi Masuda Hiroaki Setoguchi Koki Nagasawa Shigeru Fukumoto Masae Iwamoto Ishihara Rei-ichi Miura Leiko Mizusawa Ken-ichi Hiratsuka Shota Sakaguchi

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.21-00021, (Released:2021-06-18)

参考文献数

20

被引用文献数

2

---

Arnica mallotopus is a perennial herb endemic to the snowy regions of Japan. At the southern edge of its distribution, in Kyoto Prefecture, overgrazing by sika deer and decreased snowfall have resulted in the rapid decline of A. mallotopus populations. Therefore, there is an urgent need for a conservation genetic analysis of the remaining local populations. In this study, we first developed 13 EST-SSR markers to evaluate genetic variation in A. mallotopus. The average number of alleles per locus was 5.33. Genetic analysis using these markers showed that the investigated samples were classified into two groups corresponding to landscape structure. One group isolated from a tributary of the Yura River showed a strong population bottleneck signal, likely resulting from founder effects and subsequent drifts. On the other hand, the genetic diversity of the second group in the main distribution along the Yura River was higher and less inbred. Overall, our assessment suggested recognizing the two genetic groups as management units in conservation programs for the threatened populations.