- Research Article
- 10.1266/ggs.25-00085
- May 1, 2026
- Genes & genetic systems
- Shikha Singh + 2 more
Cold acclimation, defined as gradual habituation to low temperatures by exposure to moderately cold temperatures for several days, is known to enhance an organism's cold tolerance and facilitate its adaptation to seasonal temperature changes in temperate regions. The present study focuses on the evolution of the cold acclimation response in Drosophila albomicans, which rapidly expanded its distribution from tropical Southeast Asia to the Japanese main islands in the mid-1980s. This research aims to elucidate the genetic mechanisms underlying cold acclimation through gene expression changes. The gene expression changes due to cold acclimation were compared among five strains with different genetic backgrounds to identify the genes involved in these processes. High-throughput mRNA sequencing was employed to identify differentially expressed genes (DEGs) in strains from China, Taiwan and Japan under cold acclimation and control conditions. The results suggest that the actin genes play a critical role in cellular functions at low temperatures. A reduction in the expression of mElo is likely to result in decreased levels of C18 fatty acids, thereby enhancing cellular cold tolerance. Furthermore, this study highlights the universality and diversity of gene expression changes in response to cold acclimation. While many DEGs shared by all five strains were genes involved in metabolic pathways, many strain-specific DEGs were genes involved in gene regulation. This suggests that genes with critical roles in fundamental cellular and physiological processes are subject to evolutionary constraints, whereas those involved in regulatory functions or responding to local environmental conditions undergo rapid evolution to exhibit significant variability. These results provide insight into the genetic mechanisms of environmental adaptation and population expansion in nature.
- Research Article
- 10.1266/ggs.26-00012
- Apr 10, 2026
- Genes & genetic systems
- Kenji Fukunaga + 4 more
We clarified the phylogeny and population structure of foxtail millet (Setaria italica (L.) P.Beauv.) landraces using ddRAD-seq, which also enabled us to focus in detail on Japanese landraces. The results were compared with those of previous phylogenetic studies based on transposon display and genotyping of individual genes involved in domestication and diversification under natural and artificial selection. Foxtail millet landraces were found to cluster into distinct geographical groups. The comparison revealed that certain genes, such as Heading date 1 (HD1) and polyphenol oxidase (Si7PPO), began diverging soon after domestication. In contrast, genes such as Pseudo-response regulator 37 (SiPRR37) appeared to have differentiated before geographic divergence, likely in response to environmental adaptation. However, genes such as Waxy (Wx) loci diversified after geographic separation under human selection. Implication of introgression between geographically distant groups was also observed, for example, between French and East Asian landraces. In Japan, two distinct landrace groups were identified: one closely related to Korean landraces and the other showing genetic similarity to accessions from Taiwan and the Batan Islands of the Philippines. The latter group is predominantly distributed in the Nansei Islands (Okinawa Prefecture), indicating multiple introductions and complex dispersal histories of foxtail millet in Japan.
- Research Article
- 10.1266/ggs.25-00074
- Apr 8, 2026
- Genes & genetic systems
- Yumi Yamashita + 3 more
Japanagromyza tokunagai Sasakawa 1953 (Agromyzidae, Diptera) disrupts seed reproduction of orchids by feeding on orchid fruit. This species has been feeding on orchid fruits in Japan for more than 100 years, but the recent increase in damage may be due to the spread of particularly harmful populations. In this study, we used nanopore sequencing to establish microsatellite markers for J. tokunagai to infer the cause of this fly's spreading history based on population genetic analysis of historical specimen origin and current samples. Analysis of three populations showed that all 15 loci of microsatellite markers established were polymorphic and the number of alleles ranged between 3 and 13. The markers developed in this study can be used to reveal current and past population genetic diversity and gene flow, contributing to our understanding of the population history of this parasitic fly. Further research using these markers will provide a foundation for the developing control methods for J. tokunagai and support the conservation of rare orchid plants.
- Research Article
- 10.1266/ggs.vol.100-commemoration_2026
- Jan 1, 2026
- Genes & genetic systems
- Takashi Endo
- Research Article
- 10.1266/ggs.24-00196
- Jan 1, 2026
- Genes & genetic systems
- Piyao Gao + 4 more
Neurotensin receptor 1 (NTSR1) is linked with poor prognosis in many tumors, including gastric cancer (GC). However, the exact mechanism by which NTSR1 affects GC anoikis in GC is uncharted. Therefore, we aimed to elucidate the specific mechanism by which NTSR1 participates in GC anoikis. We used qRT-PCR (quantitative reverse transcription polymerase chain reaction) to assess the levels of NTSR1 and its upstream transcription factor KLF5 (a key member of the Kruppel-like factor family) in GC tissues, and bioinformatics to analyze the signaling pathways in which NTSR1 participated. A CCK-8 kit was applied to detect the viability of GC cells under different treatments. Dual luciferase and chromatin immunoprecipitation experiments verified the binding relationship between KLF5 and NTSR1. The rate of fatty acid oxidation (FAO) was analyzed using a cell metabolism meter, and FAO-related protein expression was detected using western blot (WB). Anoikis of cells in each treatment group was detected using flow cytometry, an anoikis apoptosis kit and WB. Knocking down NTSR1 repressed the viability of GC cells, and elevated the anoikis rate and the expression of cleaved PARP and cleaved caspase-3 in GC cells. Moreover, high expression of NTSR1 upregulated the expression of CPT1 protein in FAO and increased FAO levels, thereby suppressing the occurrence of anoikis in GC cells. Addition of the FAO inhibitor etomoxir reversed the above trends. Additionally, KLF5 was highly expressed in GC. Finally, KLF5 knockdown was found to overcome the repression of the FAO pathway and to facilitate anoikis in GC cells that were overexpressing NTSR1. In summary, KLF5 affects anoikis in GC cells by targeting NTSR1 to modulate the FAO pathway. Therefore, blocking the FAO pathway regulated by the KLF5/NTSR1 axis may become a new strategy for the treatment of GC.
- Research Article
- 10.1266/ggs.vol.100-milestone_2026
- Jan 1, 2026
- Genes & genetic systems
- Tetsuji Kakutani
- Research Article
- 10.1266/ggs.25-00096
- Jan 1, 2026
- Genes & genetic systems
- Yusaku Tanaka + 6 more
VANDAL family DNA transposons are prevalent in Arabidopsis and related plants. A notable feature of VANDALs is that they can overcome epigenetic silencing from the host, using a VANC protein encoded in each VANDAL member: VANC21 protein encoded in VANDAL21 specifically accumulates on its target DNA motifs that are concentrated in the non-coding regions of this TE and induces loss of DNA methylation, transcriptional derepression, and mobilization of the element. In this study, to elucidate the mechanism of how VANC subtypes have diverged to bind specifically to their own target motifs in their cognate VANDAL subfamilies, we determined the crystal structure of VANC21 in complex with its target DNA at 2.0 Å resolution. The VANC structure adopts a globular novel fold with a Zn ion coordinated at the DNA-binding site. Interestingly, most DNA-interacting VANC residues are located in the loops but not in the conserved regions among VANC subtypes. This observation suggests that the high variability of DNA-interacting regions of VANC proteins brought about the co-evolution of VANCs and their target sequences. This rapid differentiation by co-evolution enabled VANDAL family TEs to proliferate while avoiding deleterious effects on host fitness. Therefore, our findings help to understand the adaptive evolutionary strategy for the survival of parasitic sequences.
- Research Article
- 10.1266/ggs.26-00026
- Jan 1, 2026
- Genes & genetic systems
- So Nakagawa + 3 more
The 2nd Asian Genetics Consortium Conference (AGCC 2025), entitled "Genetics in Asia: Heredity, Diversity, Discovery, and Beyond," was held in Numazu City, Shizuoka, Japan, from November 14-16, 2025. The conference was jointly organized by the Genetics Society of Japan as the leading host, together with the Genetics Societies and related organizations of the other five Asian countries (Korea, India, Singapore, Taiwan, and Thailand). A total of 72 participants attended, including 19 participants from six overseas countries and regions outside Japan. Invited speakers representing each country delivered lectures on cutting-edge research in genetics, its international significance, and future perspectives, followed by active and lively discussions. In addition, there were 30 poster presentations, mainly by young researchers, which stimulated vibrant scientific exchange. From among the presenters, one researcher received the Best Poster Award, and five researchers received Outstanding Poster Awards.
- Research Article
- 10.1266/ggs.25-00086
- Nov 5, 2025
- Genes & genetic systems
- Takumi Tsuruda + 4 more
In most eubacteria the initiator protein DnaA triggers chromosomal replication by forming an initiation complex at the origin of replication and also functions as a transcriptional regulator, coordinating gene expression with cell cycle progression. While genes regulated by DnaA are relatively well characterized in exponentially growing cells, its role in gene regulation during stationary phase remains insufficiently explored. Here, using the aquatic bacterium Caulobacter crescentus as a model, we show that C. crescentus DnaA (ccDnaA) acts as a repressor of the previously uncharacterized CCNA_00139 gene, which encodes a YifB family Mg chelatase-like AAA ATPase family protein of unknown function. Biochemical analyses reveal that ccDnaA forms multimers at this site, which may interfere with RNA polymerase access to the promoter by occupying overlapping binding sequences. Consistent with these findings, in exponentially growing C. crescentus cells the CCNA_00139 promoter is repressed in a ccDnaA-dependent manner. Notably, when cells enter stationary phase, CCNA_00139 promoter activity increases in parallel with ccDnaA clearance, supporting the idea that ccDnaA-mediated repression is relieved during this phase transition. Despite its regulated expression, deletion of CCNA_00139 did not result in any detectable growth, replication or DNA damage sensitivity phenotypes under the tested laboratory conditions, suggesting a possible role under specific environmental conditions. Given that this phase-dependent transcriptional switch may, in principle, apply to other uncharacterized ccDnaA-repressed genes, we infer that CCNA_00139, along with other such genes, form a regulatory network that supports quorum sensing or adaptation to growth phase transitions. We believe that these findings offer new insight into the potential role of bacterial DnaA in regulating gene expression in dormant or non-replicating cells across diverse bacterial species.
- Research Article
1
- 10.1266/ggs.24-00108
- Jan 1, 2025
- Genes & Genetic Systems
- Qiong Zhao + 6 more
β-sitosterol is a natural plant steroidal compound with anti-cancer properties against various tumors. This work explored the inhibitory effect of β-sitosterol on the progression of lung adenocarcinoma (LUAD) and further analyzed its targets. We applied network pharmacology to obtain the components and targets of Ganoderma spore powder. The biological functions of β-sitosterol and CHRM2 were studied using the homograft mouse model and a series of in vitro experiments involving quantitative reverse transcription polymerase chain reaction, western blot, CCK-8, flow cytometry, immunohistochemistry and immunofluorescence. The regulatory influence of β-sitosterol on the glycolysis pathway was validated by measuring glucose consumption and lactate production, as well as the extracellular acidification rate and oxygen consumption rate. We found that CHRM2 binds directly to β-sitosterol. In vitro, CHRM2 overexpression repressed the apoptosis rate and expression of apoptosis-related proteins in LUAD cells, and promoted glycolysis, while the addition of lonidamine attenuated the apoptosis-inhibiting effect conferred by CHRM2 overexpression. Furthermore, β-sitosterol hindered glycolysis as well as the growth of tumors in vitro and in vivo. CHRM2 overexpression reversed the effect of β-sitosterol on the biological behavior of LUAD cells. Our results emphasize that CHRM2 is a direct target of β-sitosterol in LUAD cells. β-sitosterol can repress the glycolysis pathway, exerting an anti-tumor effect. These findings provide new support for the use of β-sitosterol as a therapeutic agent for LUAD.