• Molecules and Cells
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• 제42권12호
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• pp.858-868
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• 2019

Shoot branching is an essential agronomic trait that impacts on plant architecture and yield. Shoot branching is determined by two independent steps: axillary meristem formation and axillary bud outgrowth. Although several genes and regulatory mechanism have been studied with respect to shoot branching, the roles of chromatin-remodeling factors in the developmental process have not been reported in rice. We previously identified a chromatin-remodeling factor OsVIL2 that controls the trimethylation of histone H3 lysine 27 (H3K27me3) at target genes. In this study, we report that loss-of-function mutants in OsVIL2 showed a phenotype of reduced tiller number in rice. The reduction was due to a defect in axillary bud (tiller) outgrowth rather than axillary meristem initiation. Analysis of the expression patterns of the tiller-related genes revealed that expression of OsTB1, which is a negative regulator of bud outgrowth, was increased in osvil2 mutants. Chromatin immunoprecipitation assays showed that OsVIL2 binds to the promoter region of OsTB1 chromatin in wild-type rice, but the binding was not observed in osvil2 mutants. Tiller number of double mutant osvil2 ostb1 was similar to that of ostb1, suggesting that osvil2 is epistatic to ostb1. These observations indicate that OsVIL2 suppresses OsTB1 expression by chromatin modification, thereby inducing bud outgrowth.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.169-173
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• 2010

Correlations between cumulus cells and germinal vesicle (GV) chromatin configuration were examined in porcine oocytes. Cumulus-oocyte complexes (COCs) were collected from 2~6 mm follicles and divided into three categories according to cumulus cell morphology. "A" group was compacted COCs with more than three cumulus cell layers. "B" group was COCs with less cumulus cell layers than "A" group. "C" group was COCs with one or less layer of cumulus cells. Cumulus cells were removed 0.1% hyaluronidase, and denuded oocytes were stained with Hoechst 33342. GV chromatin configuration was classified into GV-Con and GV-Dis. GV-Con meant that a nucleus was surrounded by condensed chromatin in a ring. GV-Dis meant that filamentous chromatin clumps were distributed in nucleus. The proportion (80.2%) of GV-Con in "A" group was significantly higher than "B" (62.0%) or "C" (44.9%). The proportion (55.1%) of GV-Dis in "C" group was significantly higher than "A" (19.8%) or "B" (38.0%). The meiotic competence of COCs was examined after 44 h culture. The proportion (90.0%) of oocytes reaching to metaphase II (M-II) in "A" group was significantly higher than "B" (76.5%) or "C" (45.5%). In conclusion, oocytes with good quality cumulus cell layers are synchronized early GV stage, and early GV stage is important for meiotic competence in pigs.

• Journal of Ginseng Research
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• 제40권3호
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• pp.251-259
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• 2016

Background: Estrogen signaling pathways are modulated by exogenous factors. Panax ginseng exerts multiple activities in biological systems and is classified as an adaptogen. Zearalenol is a potent mycoestrogen that may be present in herbs and crops arising from contamination or endophytic association. The goal of this study was to investigate the impact of P. ginseng, zearalenol and estradiol in tests on spermatozoal function. Methods: The affinity of these compounds for estrogen receptor (ER)-alpha and beta ($ER{\alpha}$ and $ER{\beta}$)-was assessed in receptor binding assays. Functional tests on boar spermatozoa motility, movement and kinematic parameters were conducted using a computer-assisted sperm analyzer. Tests for capacitation, acrosome reaction (AR), and chromatin decondensation in spermatozoa were performed using microscopic analysis. Results: Zearalenol-but not estradiol ($E_2$)- or ginseng-treated spermatozoa-decreased the percentage of overall, progressive, and rapid motile cells. Zearalenol also decreased spontaneous AR and increased chromatin decondensation. Ginseng decreased chromatin decondensation in response to calcium ionophore and decreased AR in response to progesterone ($P_4$) and ionophore. Conclusion: Zearalenol has adverse effects on sperm motility and function by targeting multiple signaling cascades, including $P_4$, $E_2$, and calcium pathways. Ginseng protects against chromatin damage and thus may be beneficial to reproductive fitness.

• Clinical and Experimental Reproductive Medicine
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• 제48권2호
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• pp.142-149
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• 2021

Objective: Bacteriospermia and urogenital infections are common problems in male infertility. This study aimed to evaluate the effects of bacteriospermia on sperm parameters and clinical outcomes in semen samples infected with two common bacteria (Staphylococcus saprophyticus and Escherichia coli) in northern Iran. Methods: Microbiological tests were performed to isolate and identify organisms from 435 semen samples from infertile couples. Semen samples were assessed according to the World Health Organization criteria. The protamine status, chromatin structure, chromatin condensation, and acrosome reaction of sperm and assisted reproductive outcomes were determined in couples with different male infertility factors. Results: Among the total cases, the two most prevalent pathogens were considered: S. saprophyticus (38.2%) and E. coli (52.9%). In the semen samples infected with E. coli, the spontaneous acrosome reaction and abnormal chromatin condensation were more common (p<0.05). Significant increases in abnormal chromatin condensation and deprotamination were seen in the presence of S. saprophyticus. In washed semen, tight adhesion between the sperm midpiece and S. saprophyticus was observed. There was also a significant decrease in the fertilization rate using semen samples infected with S. saprophyticus and E. coli during in vitro fertilization cycles (p<0.001). In addition, the presence of S. saprophyticus and E. coli in semen samples was associated with a lower likelihood of clinical pregnancy in couples with various factors of male infertility. Conclusion: Poor results of assisted reproductive techniques may be correlated with semen samples infected with two common bacteria in northern Iran.

• Molecules and Cells
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• 제45권11호
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• pp.792-805
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• 2022

Repairing damaged DNA and removing all physical connections between sister chromosomes is important to ensure proper chromosomal segregation by contributing to chromosomal stability. Here, we show that the depletion of non-SMC condensin I complex subunit H (NCAPH) exacerbates chromosome segregation errors and cytokinesis failure owing to sister-chromatid intertwinement, which is distinct from the ultra-fine DNA bridges induced by DNA inter-strand crosslinks (DNA-ICLs). Importantly, we identified an interaction between NCAPH and GEN1 in the chromatin involving binding at the N-terminus of NCAPH. DNA-ICL activation, using ICL-inducing agents, increased the expression and interaction between NCAPH and GEN1 in the soluble nuclear and chromatin, indicating that the NCAPH-GEN1 interaction participates in repairing DNA damage. Moreover, NCAPH stabilizes GEN1 within chromatin at the G2/M-phase and is associated with DNA-ICL-induced damage repair. Therefore, NCAPH resolves DNA-ICL-induced ultra-fine DNA bridges by stabilizing GEN1 and ensures proper chromosome separation and chromosome structural stability.

• Journal of Microbiology and Biotechnology
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• 제32권12호
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• pp.1515-1526
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• 2022

Eukaryotic chromatin is highly organized in the 3D nuclear space and dynamically regulated in response to environmental stimuli. This genomic organization is arranged in a hierarchical fashion to support various cellular functions, including transcriptional regulation of gene expression. Like other host cellular mechanisms, viral pathogens utilize and modulate host chromatin architecture and its regulatory machinery to control features of their life cycle, such as lytic versus latent status. Combined with previous research focusing on individual loci, recent global genomic studies employing conformational assays coupled with high-throughput sequencing technology have informed models for host and, in some cases, viral 3D chromosomal structure re-organization during infection and the contribution of these alterations to virus-mediated diseases. Here, we review recent discoveries and progress in host and viral chromatin structural dynamics during infection, focusing on a subset of DNA (human herpesviruses and HPV) as well as RNA (HIV, influenza virus and SARS-CoV-2) viruses. An understanding of how host and viral genomic structure affect gene expression in both contexts and ultimately viral pathogenesis can facilitate the development of novel therapeutic strategies.

• Clinical and Experimental Reproductive Medicine
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• 제44권4호
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• pp.201-206
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• 2017

Objective: The aim of this study was to compare the efficacy of swim-up and density gradient centrifugation (DGC) for reducing the amount of sperm with fragmented DNA, sex chromosome aneuploidy, and abnormal chromatin structure. Methods: Semen samples were obtained from 18 healthy male partners who attended infertility clinics for infertility investigations and were processed with swim-up and DGC. The percentages of sperm cells with fragmented DNA measured by the sperm chromatin dispersion test, normal sex chromosomes assessed by fluorescence in situ hybridization, and abnormal chromatin structure identified by toluidine blue staining were examined. Results: The percentage of sperm cells with fragmented DNA was significantly lower in the swim-up fraction (9.7%, p= 0.001) than in the unprocessed fraction (27.0%), but not in the DGC fraction (27.8%, p= 0.098). The percentage of sperm cells with normal X or Y chromosomes was comparable in the three fractions. The percentage of sperm cells with abnormal chromatin structure significantly decreased after DGC (from 15.7% to 10.3%, p= 0.002). The swim-up method also tended to reduce the percentage of sperm cells with abnormal chromatin structure, but the difference was not significant (from 15.7% to 11.6%, p= 0.316). Conclusion: The swim-up method is superior for enriching genetically competent sperm.

• 대한의생명과학회지
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• 제8권3호
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• pp.179-184
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• 2002

We investigated the morphological changes and TUNEL reaction of apoptotic cells in the liver of D-galactosamine (20 mg/mouse) and lipopolysaccharide (5 $\mu\textrm{g}$/mouse)-treated 30 mice (BALB/c), and in additioa also of apoptotic cells in kidney and spleen. The livers and other some organs of mice at 6, 12, 24, 48 and 72 hrs after treatment were collected and were fixed with 10% neutral formalin and paraffin sections were stained with hematoxylin-eosin or terminal deoxynucleotidly transferase-mediated dUTP nick end labeling (TUNEL) method. Morphological changes in apoptotic hepatocytes were chondensation of nuclei and density of cytoplasms, then the margination and pyknosis of chromatin, the formation of half-moon- or horse-shoe- or ship-like shapes of condensed chromatin mass, lastly formation of apoptotic bodies, disappearance of nuclear envelopes, decrease of stainability, then lysis and disappearance of apoptotic bodies. TUNEL positive reactions of hepatocytes were appeared first moderate in uncondensed hepatocytes, severe in condensed hepatocytes, moderate in chromatin-marginated hepatocytes. These reactions also were appeared moderate in hepatocytes with half-moon- or horse-shoe- or ship-like pyknotic chromatin mass or apoptotic bodies, and mild or negative in hepatocytes with lysed apoptotic bodies or with disappeared nuclear envelopes. Consequently these results suggested that TUNEL positive reactions of hepatocytes appeared at more early stages than appearance of chromatin condensation and disappeared at more early stage than disappearance of histological findings of apoptosis. We also confirmed that the differentiation of apoptotic cells from normal healthy cells of Kupffer cells and vascular endothelial cells in liver, reticular cells and lymphocytes in spleen and epithelial cells of tubules and ducts in kidney was impossible in H-E preparations but was possible in TUNEL preparations.

• Clinical and Experimental Reproductive Medicine
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• 제45권1호
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• pp.17-24
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• 2018

Objective: To investigate sperm chromatin/DNA integrity, global DNA methylation, and DNMT mRNA transcription in men with oligoasthenoteratozoospermia (OAT) compared with normozoospermic men. Methods: Semen samples from 32 OAT patients who comprised the case group and 32 normozoospermic men who comprised the control group were isolated and purified using a standard gradient isolation procedure according to World Health Organization criteria. DNMT1, DNMT3A, and DNMT3B transcripts were then compared between groups using real-time quantitative reverse-transcription polymerase chain reaction. Global DNA methylation in sperm was determined by an enzyme-linked immunosorbent assay. Protamine deficiency and the proportion of apoptotic spermatozoa were evaluated using chromomycin A3 (CMA3), aniline blue (AB), and toluidine blue (TB) staining, as well as the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The p-values < 0.05 were considered to indicate statistical significance. Results: Significantly higher proportions of AB+, TB+, CMA3+, and TUNEL+ spermatozoa, as well as DNMT3A and DNMT3B transcription, were found in the OAT group. Positive correlations were detected between sperm parameters, DNA/chromatin damage, and DNMT3A and DNMT3B transcripts. Global DNA methylation was significantly higher in the OAT patients and had a significant correlation with abnormal results of all sperm chromatin integrity tests, but was not associated with DNMT1, DNMT3A, or DNMT3B expression. Conclusion: Oligoasthenoteratozoospermic men showed abnormal sperm parameters, abnormal chromatin/DNA integrity, and a higher global DNA methylation rate, as well as overexpression of DNMT mRNA.

• 한국동물학회지
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• 제8권2호
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• pp.37-41
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• 1965

The frequency and pattern of sex chromatin in primary cultured cells of kidney cortex of cats and guinea-pigs, and muscle of chick embroys were examined and compared to those of in vivo condition, with special reference to the various cultured stages. 1. In cat, the frequencies of sex chromatin positive I of peripheral position were average 62.7% in female, and 15% in male, whereas those of non-peripherla position were 5.8% in female and 0.1% in male. The incident proportion between them showed a marked difference-approximately 10 times higher in female than male. These results failry indicated that a distinct nuclear dimorphism with regard to the sex chromatin positive I was established in cultured cells. The position of sex chormatin was usually peripheral location. The tendency of frequencies , with reference to the cultured stages, was low count in primary extracted and initial stage cells , but it showed a peaked frequency in 10-13 days after primary culture, and after that the frequencies were decreased gradually. Compared between I vitro and in vivo condition of the same tissues, the cells in vivo exhibited the sex chromatin in high frequency at the peak showed stage. 2. In guinea-pig , the frequencyies of peripheral positive I were 36.8% in female and 6.3% in male, while non-peripheral positions were 6.1% in female and 3.5% inmale. Its incident was a rate of nearly 4 times higher in female than male. The nuclear dimorphism was also established in cultrued cells of guinea-pig. The position and the incident frquency showed a similar pattern as in cat except the primary extracted cells. 3. In chick embryo, the frequencies of sex chromatin positive I of peripheral position were 38.2% in female, and 18.3% in male, non-peripheral position, however, was hardly to find. These results suggest that the definite sexual dimorphism was unable to find in chick embryo cultured cells. The position and the incident tendency were a similar pattern as in above mammals and the frequency was higher in vitro cells.