• Environmental Analysis Health and Toxicology
• /
• v.19 no.3
• /
• pp.235-240
• /
• 2004

본 연구는 비만세포의 일종인 RBL-2H3 세포주에 대한 hexamethylene bisacetamide (HMBA)의 세포독성 유도 기전이 telomerase의 활성과 관계가 있다는 것에 대한 보고이다. RBL-2H3 세포주에 5mM HMBA를 처리시 그 세포주의 세포성장이 억제 되었다. 기전연구로서 HMBA는 telomerase활성을 억제 하였으며 RT-PCR에 의한 결과 telomerase mRNA발현의 억제에 의한 것이었다. Madl은 telomerase의 발현을 억제하는 억제인자로 잘 알려져 왔으며 이를 확인해본 결과 Madl은 발현은 유의성있게 증가 되었다. 이를 종합해보면, HMBA에 의한 RBL-2H3 세포주에 대한 세포독성은 Madl 발현의 증가에 따른 telomerase발현의 억제에 기인하는 것으로 밝혀졌다.

• Journal of Food Hygiene and Safety
• /
• v.34 no.5
• /
• pp.447-453
• /
• 2019

In this study, the contamination of 4 types of heavy metals (lead, cadmium, arsenic, and mercury) was monitored in 80 seaweeds and their processed products, and a food safety assessment was also carried out for these heavy metals. Lead, cadmium and arsenic were analyzed by ICP-OES and mercury was analyzed by mercury analyzer. The detection ranges of heavy metals were found as follows: Pb (N.D-0.802 mg/kg), Cd (N.D-0.759 mg/kg), As (0.134-17.296 mg/kg), and Hg (0.0005-0.0331 mg/kg). Pb and Hg showed no significant differences among seaweeds whereas Cd and As were significantly higher in the species hizikia fusiforme (P<0.05). Food safety assessment from seaweed intake was measured by PTWI (Provisional Tolerable Weekly Intake), PTMI (Provisional Tolerable Monthly Intake), and MADL (Maximum Allowable Daily Body Load) as set by JECFA (Joint FAO/WHO Expert Committee on Food Additives). Pb and Hg were 0.197%, 0.036% of PTWI respectively, while Cd was 1.877% of PTMI and As was 0.619% of MADL. Therefore, it was found that heavy metal levels of seaweed were low and was considered to be safe for consumption.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2002.10a
• /
• pp.162-172
• /
• 2002

Schizosaccharomyces pombe is suited for the study of cytokinesis as it divides by forming a septum in the middle of the cell at the end of mitosis. To enhance our understanding of the cytokinesis, we have carried out a genetic screen for temperature-sensitive S. pombe mutants that show defects in septum formation and cell division. Here we present the isolation and characterization of a new temperature-sensitive mutant, sun1(septum uncontrolled), which undergoes uncontrolled septation during cell division cycle at restrictive temperature $(37^{\circ}C)$. In sun1 mutant, actin ring and septum are positioned at random locations and angles, and nuclear division cycle continues. These observations suggest that the sun] gene product is required for the proper placement of the actin ring as well as precise septation. The sun] mutant is monogenic recessive mutation unlinked to previously known various cdc genes of S. pombe. In a screen for $sunl^+$ gene to complement the sun] mutant, we have cloned a gene, $susl^+$(suppressor of sun1 mutant), that encodes a protein of 689 amino acids. The predicted amino acid sequence of $susl^+$ gene is similar to the human hMadlp and Saccharomyces cerevisiae Mad1p, a component of the spindle checkpoint in eukaryotic cells. The null mutant of $susl^+$ gene grows normally at various temperatures and has the increased sensitivity to anti-microtubule drug, while $susl^+$ mutant shows no sensitivity to microtubule destabilizing drugs. The putative S. pombe Sus1p directly interacts with S. pombe Mad2p in yeast two-hybrid assays. These data suggest that the newly isolated susr gene encodes S. pombe Mad1p and suppresses sun] mutant defective in controlled septation in a cell division cycle.