Fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is a polyphagous agricultural pest that damages about 80 species of plants. It mainly damages Poaceae and plants used as food resources for humans. Its original habitat is the American continent, but it unintentionally settled in tropical and subtropical Asia, including Africa, India, and Sri Lanka. It occurs every year even in southern China, which is geographically adjacent to the Korean Peninsula, causing damage to crops. In Korea, it was first discovered on Jeju Island in June 2019 and is being discovered every year in Jeju and some inland areas. In 2023, there were a total of 13 discoveries, including those in the Jeju and Jeonbuk regions. Quarantine agency identified the maternal genotypes of all currently discovered individuals using COI and identified differences in genetic traits between individuals using the sex-related Z-chromosome. For comparison with the information on the individuals that invaded the country, 15 individuals from Guangxi and Guangdong provinces in China were collected and secured. Through the analysis of overseas samples, a database has been added to compare genetic information with domestic invasive species, and the reliability of the analysis is expected to increase.

Helicoverpa assulta (Lepidoptera: Noctuidae) exhibits a specialized herbivorous diet, primarily targeting select Solanaceae plants. Despite its significant economic impact as a pest, causing substantial harm to crops like hot pepper and tobacco, it has received comparatively limited attention in research compared to its generalist counterparts, H. armigera and H. zea.We introduce a chromosome level genome assembly using a Korean H. assulta (Pyeongchang strain, K18). This assembly was achieved through a combined approach utilizing Nanopore long-read sequencing (approximately 78X coverage) and Illumina NovaSeq short-read sequencing (approximately 54X coverage). The total assembled genome spans 424.36 Mb, designated as ASM2961881v1, comprises 62 scaffolds, with 98.7% of the genome contained within 31 scaffolds, confirming the insect's chromosome count (n = 31). The completeness of the assembly is reflected in BUSCO assessment, with values reaching 99.0%, while the repeat content accounts for 33.01%, and 18,593 CDS were annotated. Additionally, 137 genes were identified within 15 orthogroups that have rapidly expanded in H. assulta, while 149 genes in 95 orthogroups have rapidly contracted. This genome draft serves as a valuable resource to explore various aspects of the specialist's biology, enabling research into host-range evolution, chemical communication, insecticide resistance, and comparative investigations with other Heliothine species.

Rose is one of the most economically important ornamental crops worldwide. Although rose products are widely used, limited genetic and genomic data from this species is available. Fundamental genetic knowledge can accelerate the development of superior rose germplasms. In the present study, we explored the genetic data (e.g., chromosome numbers, total chromosome length, and ploidy level) of 39 rose cultivars using conventional cytogenetic methods. Of the 39 rose cultivars tested, 36 (92.3%) were tetraploid (2n = 4x = 28). ‘Rosada,’ ‘Rosemarin,’ and ‘Hanmaum’ were diploid (2n = 2x = 14), triploid (2n = 3x =21), and tetraploid-based aneuploid (2n = 4x = 28 + 2), respectively. The total chromosome length ranged from 46.03 ± 0.55 μm in ‘Rosada’ (2x) to 138.51 ± 0.92 μm in ‘Christoper’ (4x). The chromosome information obtained in this study will be useful for rose breeding and germplasm evaluation.

Because of their attractive and colorful flowers, many species from the genus Aster serve as garden plants. Chrysanthemum owes its popularity to its ornamental and medicinal herb value. It can be used as a cut flower, potted plant, vegetable, and herbal tea. Plant breeders have attempted to identify the available species and produce new cultivars to improve the quality of chrysanthemum for commercial purposes. The use of cytogenetic studies has paved the way for identifying compatibility, ancestry, and other useful information for this undertaking. Thus, an investigation was conducted into the chromosome numbers of 23 wild Asteraceae species in Republic of Korea to determine their genetic characteristics and variations. The somatic chromosome spread has been used for chromosome counting. The results revealed that Asteraceae species have a chromosome range from 18 (diploid) to 54 (hexaploid). These findings provide primary and important information on the chromosome numbers in chrysanthemum plants that can be used to select the right variety for cultivation.

X-chromosome inactivation is one of the most complex events observed in early embryo developments. The epigenetic changes occurred in female X-chromosome is essential to compensate dosages of X-linked genes between males and females. Because of the relevance of the epigenetic process to the normal embryo developments and stem cell studies, X-chromosome inactivation has been focused intensively for last 10 years. Initiation and regulation of the process is managed by diverse factors. Especially, proteins and non-coding RNAs encoded in X-chromosome inactivation center, and a couple of transcription factors have been reported to regulate the event. In this review, we introduce the reported factors, and how they regulate epigenetic inactivation of X-chromosomes.

The Y chromosome is a type of sex chromosome existing primarily in male mammalian species. The Y chromosome passes through the male gamete and determines male sex in humans, non-human primates, and other mammals. The mammalian Y chromosome varies from the X chromosome and the rest of the chromosomes primarily by size and its male sex-determining/spermatogenesis function. In the Y chromosome, male sex-determining function is exclusively located on the short arm, while the spermatogenesis function is distributed widely on the short and long arm. Deletions or mutations particularly in the male-specific region of Y chromosome (MSY) may cause male infertility. During the last few decades, researchers put forth an enormous effort to discover Y chromosome specific genes, and their encoded RNAs and proteins in humans, primates, and rodents. As a result, most of the genes and encoded proteins responsible for male-sex determination, testis development, and spermatogenesis have been discovered in humans, however not well established in non-human primates and rodents. Also, there might be a percent of proteins missing in human Y chromosome. The aim of this study is to annotate the proteins that encoded on the Y chromosome of humans, chimpanzee, and mouse using extensive bioinformatics tools. The human (annotation release 107), chimpanzee (annotation release 103), and mouse (annotation release 105) proteins were first retrieved from the National Center for Biotechnology Information (NCBI) eukaryotic genome annotation resource database. Then, the annotated human proteins (66 proteins) were compared with the core databases of human proteome project such as neXtProt, PeptideAtlas, and the Human Protein Atlas. The X-homologous of human Y chromosome-encoded proteins were searched using the NCBI Protein BLAST program. The cellular pathways and protein-protein interactions involving human Y chromosome-encoded proteins were searched using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping database, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and the Pathway Studio software. Finally, the human Y chromosome-encoded protein homologs/orthologs in chimpanzee and mouse were analyzed using the NCBI bl2seq program. This analysis resulted a significant number of homologous/orthologous proteins between human, chimpanzee and mouse. Our findings provide the scientific community with updated information on the Y chromosome-encoded proteins in humans, chimpanzee, and mouse.

The genus Lilium has a huge nuclear genome size (approximately 13,400 to 46,900 Mbp), implying that Lilium genome is composed of a larger amount of repetitive sequences. To understand the organization of plant genome is required to observe repetitive DNA sequences found in the Lilium chromosome. In this study, Cot DNA analysis was introduced, in which repeated DNAs were assessed. The Cot analysis revealed that Cot-1 DNAs were a target region that contained highly and moderately repetitive sequences. In addition, Cot-1 DNA as a probe in fluorescence in situ hybridization (FISH) was used to detect somatic chromosomes at the metaphase stage of diploid (2x) Lilium tigrinum. The FISH analysis showed that bright fluorescent signals on the Cot-1 DNA were sporadically distributed in all over the L. tigrinum-chromosomes. However, relatively weak signals were displayed in nucleolarorganizing regions (NORs) of chromosome #1, #2, and #7 as follows: centromere and peri-centromere regions of all chromosomes; distinct DAPI band region in long arm of chromosome #8; and short arm of chromosome #7, #8, #9, #10, #11, and #12. In conclusion, the random Cot-1 DNA distribution pattern has proven that L. tigrinum genome is composed of dispersed repetitive DNAs.

Cattle breeds were classified previously into three different haplogroups (Y1 and/or Y2 in Bos taurus and Y3 in B. indicus) based on Y chromosome-specific polymorphisms. In particular, a rapid and unambiguous classification method was reported recently. However, a haplogroup classification of Korean native cattle breeds has not been reported. In this study, 196 animal samples from four Korean native cattle breeds (Hanwoo, Chikso, Heugu, and Jeju black cattle) and six exotic breeds were used to determine the Y chromosome-specific haplogroup classification. We amplified an 81 bp indel region within intron 26 of the USP9Y gene and performed electrophoresis to classify the Y1 and Y2 haplogroups. Moreover, enzyme digestion was carried out with the SspI restriction enzyme to classify the Y2 and Y3 haplogroups. Finally, sequence variation in each haplogroup was confirmed by DNA sequencing. All animals in the four Korean native cattle and two exotic breeds (Charolais and Simmental) belonged to the Y2 haplogroup. Three other exotic breeds (Holstein, Angus, and Hereford) belonged to Y1 haplogroup. Japanese black cattle were divided into both the Y1 and Y2 haplogroups. The Y3 haplogroup corresponding to B. indicus was not found in this study. In conclusion, Korean native cattle breeds originated from B. taurus without introduction from B. indicus. In addition, they showed the same paternal heredity pattern which belonged to only Y2 haplogroup. These results can be used to investigate the origin of Korean native cattle breeds.

세포유전학 연구는 유전학과 세포학으로부터 발생된 학 문으로 염색체의 수, 구조, 행동 등의 염색체 연구를 기 본으로 하는 분야이다. 1980년대 이후 분자생물학적 기 술의 적용으로 새로이 발전하였으며 현재는 유전체 해 독 연구와 함께 다양한 연구분야에 적용되고 있다. 세 포유전학적 연구를 위한 연구기법은 전통염색법에 의한 banding 기법, fluorescence in situ hybridization(FISH), genomic in situ hybridization(GISH), fiber FISH, BAC-FISH 기법 등이 있으며 이들은 기초 핵형을 분석 하는 연구 분야에서부터 유전자의 위치를 탐색하는 응용 연구분야까지 다양하게 이용되고 있다. 현재 화훼연구에 있어서 세포유전학적 연구의 이용은 (1) 배수성 검경을 통한 교배육성의 기초자료 제공, (2) FISH 핵형분석을 통 한 정밀한 핵형분석, (3) GISH 기법을 이용한 게놈 이 입분석, (4) microdissection 방법을 이용한 유전체 분석, (5) GM 작물에서 외래유전자의 위치 추적 등에 적용될 수 있다. 그러나 국내의 화훼연구에서의 세포유전학적 연 구는 아직은 크게 활성화 되지 않았으며 추후 유전체분 석연구 응용을 위해서는 다양한 작물과 다양한 기술의 적 용이 필요하다. 따라서 본 논문에서는 화훼연구에서의 세포유전학의 개념과 필요성, 연구의 이용에 대해 논하고 자 한다.

Several studies have been conducted with the aim of establishing embryonic stem cell lines from porcine embryos. However, most researchers to date have found it difficult to maintain an ES-like state in derived cell lines, with the cells showing a strong tendency to differentiate into an epithelial or EpiSC-like state. We have also been able to derive cell lines of an EpiSC-like state and a differentiated non-ES-like state from porcine embryos of various origins, including invitro fertilized(IVF), in vivo derived, IVF aggregated and parthenogenetic embryos. In addition, we have generated induced pluripotent stem cells(piPSCs) via plasmid transfection of reprogramming factors (Oct4, Sox2, Klf4 and c-Myc) into porcine fibroblast cells. X chromosome inactivation (XCI) have recently been addressed as a hallmark to determine whether pluripotent cell is naïve or primed state. In this study, we could confirm the X chromosome inactivation status in female cell lines as well as marker expression, pluripotency and of our Epi- SC-like pESC lines along with our piPSC line. All of our cell lines showed AP activity and expressions of the genes Oct4, Sox2, Nanog, Rex, TDGF1, bFGF, FGFR1, FGFR2, Nodal and Activin-A involved in pluripotency and signaling pathways, XCI in female cell lines, in vitro differentiation potential and a normal karyotype, thus displaying similarities to epiblast stem cells or hES cells. Therefore, it may be inferred that, as a non-permissive species, the porcine species undergoes reprogramming into a primed state during the establishment of pluripotent stem cell lines.

In mammals, the meiosis division in testes produces equal numbers of two different types of gametes: X chromosome-bearing sperm (X-spermatozoa) and Y chromosomebearing sperm (Y-spermatozoa), which have equal potential to fertilize the oocytes. Therefore, the expected 1: 1 sex ratio is observed. However, under some conditions like endocrine disruptors (EDs) exposure the sex ratio is deviated than the expected with more males or more females. And recently many hypotheses have been postulated to explain the mechanism of sex ratio deviation; however none of them introduced a proven experimental explanation. To solve this enigma, we hypothesized that the differences between X- and Y-spermatozoa survivability under specific conditions due to differences in their chromosome contents are the key leading to the sex ratio alteration. To examine our hypothesis, we combined two techniques; first, hypo-osmotic swelling (HOS) test that was applied to test viability of spermatozoa and second, fluorescence in situ hybridization that was applied on HOS-treated spermatozoa to define sex chromosome composition. In the present study, human spermatozoa were incubated with a group of EDs represent a widespread chemicals in the environment bisphenol A (BPA, 100 μM), nonylphenol (NP, 10 μg/ml), 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, 2.5 μg/ml), genistein (Gen, 100 μM), and the following pesticides, dibromochloropropane (DBCP, 10 μg/ml), atrazine (Atraz, 500 μM), and diazinone (Diaz, 500 μM) for 6 hr at 37℃ in 5% CO2. Then, the viability of spermatozoa and their sex chromosome contents were evaluated simultaneously. Among seven chemicals studied only four chemicals (Atraz, DBCP, TCDD, and Diaz) significantly decreased Y-sperm viability when compared to those of X-spermatozoa in the same treatment group and viability of Y-spermatozoa when compared to those in the negative and positive (DMSO) control groups (p<0.05). Also, in these four treatment groups the sex ratio of live sperm population was significantly lowered compared to the control groups (p<0.05). Otherwise, Gen, BPA, and NP did not show any significant effect on viability of Yspermatozoa or decreasing sex ratio in live sperm population as compared to the control groups. It has been proven that TCDD, DBCP, and the pesticides decrease the sex ratio, but the same effect was not observed in case of Gen, BPA, and NP. From the present findings, there is no doubt that the EDs may alter sex ratio via decreasing Y-spermatozoa viability.

In general, the blood cell culture is a common method for animal chromosome preparation. However, every animal and its cells have unique physiological characteristics and functions. Hence, it is very difficult to find the suitable method of chromosome preparation using animal lymphocyte culture. This study was carried out to find the suitable method of chromosome preparation using lymphocytes cultures in mammalians and aves including cattle, rat, mouse and chicken. To seek the optimal method of lymphocyte culture in each animal, 23 factorial experiment was designed. The design evaluated three main effects in culture duration, kinds of mitogen supplements and colcemid exposure time with two levels within each effect. The mitotic index and the score of chromosome morphology were analyzed. In results, the suitable methods of lymphocyte culture for chromosome preparation were 72 hours culture, pokeweed mitogen(PWM) supplement and 90 minutes of colcemid exposure in cattle, 72 hours culture, PWM supplement and 50 minutes of colcemid exposure in chicken, 96 hours culture, concanavalin A supplement and 90 minutes of colcemid exposure in rat, and 72 hours culture, PWM supplement and 50 minutes of colcemid exposure in mouse, respectively. In conclusion, kinds of mitogen, culture duration and colcemid exposure time significantly affected the mitotic index and chromosome morphology in animal lymphocyte culture. The interaction effects between/among treatment factors were also statistically significant.

In the present study, effects of concentration and time of culture in presence of roscovitine on nuclear maturation and meiotic spindle configuration, chromosomal alignment were examined in porcine oocytes. In experiment 1, porcine cumulus oocyte complexes (COCs) were cultured at in a 5% atmosphere in North Carolina State University 23 (NCSU-23) supplemented with 25, 50, 75 or roscovitine for 22 h and then were cultured for additional 22 h after removal of roscovitine. Nuclear maturation and morphology of the meiotic spindle and chromosomal alignment were examined to determine the optimal concentration of roscovitine in oocyte maturation. In experiment 2, COCs were cultured in NCSU-23 supplemented with roscovitine for 17, 20, 27 or 42 h and then an additional 22 h without roscovitine was followed to determine the optimal time of culture. The optimal concentration of roscovitine to arrest and resume meiosis of porcine oocyte was by examining nuclear status (p<0.05) and normal spindle and chromosome configuration. The optimal time of culture in presence of roscovitine to arrest meiosis of porcine oocyte was 17 h (p<0.05), although MII rates and normal morphology of the meiotic spindle and chromosomal alignment were not significantly different among various times of culture. In conclusion, the optimal concentration and time of culture in presence of roscovitine to arrest porcine oocytes are and 17 h, respectively.

The paternal sex ratio (PSR) chromosome is considered as an extremely selfish genetic element. It has only been found in the two hymenopteran insects- Nasonia and Trichogramma- with haplodiploid sex determination. When an egg is fertilized by sperm bearing PSR, the paternal genome is destroyed by PSR soon after fertilization resulting in haploid restoration and the egg develops into a male with only the maternal genome and PSR itself. Recently PSR is paid much attention, since it may be used for controlling haplodiploid pests. PSR can be successfully transferred from its natural host, T. kaykai to the novel host, T. deion. In the two hosts another sex ratio distorter, Wolbachia, is found. Wolbachia is a cytoplasmically inherited bacterium that induces parthenogenesis in this genus resulting in female offspring production without fertilization. The transmission efficiency of PSR in T. deion is lower than that in T. kaykai and is negatively influenced by the Wolbachia infection. The results show that 1) there is a negative host genetic background effect on the transmission of PSR in the novel host, 2) the transmission efficiency becomes even lower, when PSR males are infected with Wolbachia. The results imply that complex interactions among the bacterium, PSR and the species specific genetic background.

This study was conducted to examine the protein kinase inhibitors, 6-dimethylaminopurine (DMAP) and cycloheximide (CHXM) on the development and chromosome constitution of porcine parthenogenetic embryos. In vitro matured oocytes were activated by electric stimuli (ES) or a combination of ES with culture in 2 mM DMAP or 10 μg/ml CHXM for 4 hr. Activated oocytes were cultured in PZM-3 for 6 days. Some 1-cell embryos and blastocysts were fixed by air dry method to analyze the chromosome constitutions and/or total cell number. Blastocyst development of DMAP-treated group (26.7%) was significantly higher (p<0.05) than those of CHXM-treated and ES control groups. Ploidy in 1-cell stage embryos was not different among groups (77.3 to 81.0%), however, proportion of diploid chromosome constitutions was high in DMAP-treated group (61.9%, p<0.05). In the blastocyst stage, proportion of diploid chromosome plates was significantly high in DMAP-treated group (64.2%, p<0.05), and proportion of abnormal chromosome plates was higher in CHXM-treated group (36.6%, p<0.05) than DMAP-treated group (28.3%,). Proportion of embryos with abnormal chromosome constitutions was slightly increased by DMAP (40.0%) and CHXM (42.1%) treatment due to the increasing of mixoploid (47.4 and 52.0%). The present study shows that the DMAP treatment increase the development of porcine parthenotes. However, parthenogenetic activation by ES or combined treatment with ES and DMAP or CHXM detrimentally affects the chromosome constitutions of porcine parthenotes during early embryonic development, leads to increased abnormal ploidy in the blastocyst stage.