• Mycobiology
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• 제30권2호
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• pp.61-64
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• 2002

A Monokaryotic strain G8M without clamp connections was isolated from germinated basidiospore that was obtained from cultivated fruit body. Strain G8M was used as a tester isolate for 'dikaryon-monokaryon mating'(di-mon mating) with the strains of Ganoderma lucidum, G6 and G35(Korean wild strains), G3(Taiwan), G4(Canada), G15(America), G. oregonense G24, G. resinaceum G28, G. oerstedii G23, and G. subamboinense G29. Isolate G8M was compatible to Korean strains G6 and G35, but was incompatible to foreign strains G3, G4, or G15. Compatible reactions between strains were readily observed macroscopically. Clear barrage lines formed between incompatible strains. These clear lines were not apparent in compatible di-mon matings. The Korean strains were morphologically distinct; they did not form any chlamydospores, and stopped growth at $35^{\circ}C$. The strains of G. lucidum from Korea may be considered as different species from Taiwan, Canadian and American cultures.

• Mycobiology
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• 제39권4호
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• pp.235-242
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• 2011

In contrast to the nuclear genome, the mitochondrial genome does not follow Mendelian laws of inheritance. The nuclear genome of meiotic progeny comes from the recombination of both parental genomes, whereas the meiotic progeny could inherit mitochondria from one, the other, or both parents. In fact, one fascinating phenomenon is that mitochondrial DNA in the majority of eukaryotes is inherited from only one particular parent. Typically, such unidirectional and uniparental inheritance of mitochondrial DNA can be explained by the size of the gametes involved in mating, with the larger gamete contributing towards mitochondrial DNA inheritance. However, in the human fungal pathogen Cryptococcus neoformans, bisexual mating involves the fusion of two isogamous cells of mating type (MAT) a and MAT${\alpha}$, yet the mitochondrial DNA is inherited predominantly from the MATa parent. Although the exact mechanism underlying such uniparental mitochondrial inheritance in this fungus is still unclear, various hypotheses have been proposed. Elucidating the mechanism of mitochondrial inheritance in this clinically important and genetically amenable eukaryotic microbe will yield insights into general mechanisms that are likely conserved in higher eukaryotes. In this review, we highlight studies on Cryptococcus mitochondrial inheritance and point out some important questions that need to be addressed in the future.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.418-422
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• 2017

공개된 자료들을 바탕으로 NASA의 표준 착화기 NSI-1,2,3의 간략한 성능규격 비교와 함께 NSI에 연결되는 전기 커넥터의 규격을 비교하였다. NSI-1,2에 연결되는 커넥터의 규격은 MSFC-40M38298과 MIL-DTL-26482, series1이며, NSI-3에 연결되는 커넥터의 규격은 MIL-DTL-38999, series3이다. 전체적인 내환경 성능은 낮음에서 높음 순서로 MIL-DTL-26482, series1/MSFC-40M38298/MIL-DTL-38999, series3 이다. 특히, 고충격, 고진동 환경에서 착화기를 사용하여야 한다면 NSI-3의 커넥터 규격인 MIL-DTL-38999, series3의 커넥터를 사용하는 것이 적절할 것이다.

• Toxicological Research
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• 제12권1호
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• pp.93-99
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• 1996

The effect of KTC-1, a new semisynthetic rifamycin antituberculous drug, on general toxicity, reproductive capability and fetal development was investigated in Sprague-Dawley rats. Male rats were administered KTC-1 with mashed feed from 63 days before mating to the end of mating period, and female rats were given from 14 days before mating to day 7 of gestation at dose levels of 0, 375, 750, and 1,500 ppm. The females were sacrificed on day 21 of gestation for examination of their fetuses. At 1,500 ppm, a reduction in body weight gain and testis atrophy were observed in male rats. Histological examination revealed testicular atrophy, absence or decrease of germinal cells, and vacuolization of Sertoli cells in testis. A reduction in body weight gain, a decrease in food consumption were found in female rats. In addition, decreases in the number of corpora lutea, iraplantations, and the litter size of live fetuses were seen. Mating, fertility, and pregnancy performances were also affected. There were no external abnormalities observed by examination of fetuses. At 750 ppm, a reduction in the body weight gain of male and female rats and decreases in the number of implantations and litter size were found. At 375 ppm, no treatment-related effects were observed. The results suggest that the no-effect dose levels (NOELs) of KTC-1 are 375 ppm for males and females on general toxicity, 750 ppm for males and females on reproductive capability, and 375 ppm for fetuses on embryonic development.

• Molecules and Cells
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• 제39권7호
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• pp.573-579
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• 2016

During copulation, male Drosophila transfers Sex Peptide (SP) to females where it acts on internal sensory neurons expressing pickpocket (ppk). These neurons induce a post-mating response (PMR) that includes elevated egg-laying and refractoriness to re-mating. Exactly how ppk neurons regulate the different aspects of the PMR, however, remains unclear. Here, we identify a small subset of the ppk neurons which requires expression of a pre-mRNA splicing factor CG3542 for egg-laying, but not refractoriness to mating. We identify two CG3542-ppk expressing neurons that innervate the upper oviduct and appear to be responsible for normal egg-laying. Our results suggest specific subsets of the ppk neurons are responsible for each PMR component.

• 한국응용곤충학회지
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• 제60권1호
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• pp.15-47
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• 2021

성페로몬은 곤충 종 특이적으로 교미신호를 전달하는 화학신호물질이다. 곤충의 촉각에는 이러한 성페로몬 화학물질을 받아들이는 특이적 수용체를 지닌다. 성페로몬이 이 수용체에 결합하면서 감각전위를 발생시키고 이는 대뇌로 전달되어 정보 인식을 통해 교미행동을 유발하게 한다. 성페로몬은 또한 해충의 발생을 모니터링하는 데 이용되어 온도발육모델과 더불어 향후 발생상황을 예측하는 데 널리 이용되고 있다. 더불어 성페로몬이 해충의 대량포획, 유살 또는 교미교란을 유발하여 직접적으로 방제에 응용된다. 본 종설은 성페로몬과 관련된 곤충 생리 및 이를 이용한 해충관리기술을 소개한다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.88.2-89
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• 2003

Changes of control efficacy of metalaxyl to potato late blight caused by Phytophthora infestans were examined in potato fields from 2001 to 2003. In 2001 and 2002, control efficacy of metalaxyl was similar to those of dimethomorph and ethaboxam. However, the control efficacy of metalaxyl were decreased to 50.3％ in 2003. Total 366 isolates of P infestans obtained from several areas in Korea from 2001 to 2003 were examined for changes of sensitivity to metalaxyl. About 6.8％ of fungal isolates examined in 2001 were sensitive, 84.1％ were intermediate resistant, 9.1％ were resistant to metalaxyl. Among the isolates collected in 2002, 3.9％ were sensitive, 75.6％ were intermediate resistant, 20.6％ were resistant to the chemical. However, among the isolates obtained in 2003, 55.9％ were intermediate resistant, 44.1％ were resistant, but none of the isolates tested were sensitive. Both A1 and A2 mating type isolate were isolated in 2002∼2003. However, all isolates collected in 2001 were A1 mating type. About 87.5％ of the isolates collected in 2002, 89.8％ In 2003 were determined as A1 mating type. The majority of the p. infestans isolates were A1 mating types. Changes of control efficacy of metalaxyl to potato late blight might be caused by the occurrence rate of moderately resistant isolates within A1 mating type.

• Asian-Australasian Journal of Animal Sciences
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• 제25권5호
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• pp.738-748
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• 2012

One of the main goals of small, medium and large farms is to improve the reproductive performance of rabbit does. Stocks of lower productivity can be improved by crossing with intensive breeds. A better nutritional status of both foetuses and suckling kits has a positive effect on their later productivity. Overfeeding young females before first mating can lead to conditions of fattiness. Using restricted feeding or higher fibre content in the feed and changing it for a higher level ad libitum feeding about one week prior to first mating leads to longer lifespan and higher productive level. Intensive reproductive rhythm creates a negative energy balance in does : they are unable to consume enough feed (energy) for the nutritional requirements of foetus and lactation, and therefore lose most of their fat reserves. Furthermore, primiparous does also expend energy because they are still growing. Under intensive conditions, the 42-d reproductive rhythm (re-mating 11 days after parturition) is recommended. Under extensive conditions, the 18 or 25-d mating interval with 35 to 42-d weaning could be suitable. On small farms, natural mating is favoured; on large farms AI is commonly employed. The main advantage of AI is the all-in, all-out system. Hormonal (PMSG) treatment is used with AI to increase receptivity on d 11. Frequent and high level PMSG use can lead to higher anti-PMSG antibody rates. Lower level (max. 20 IU) and less frequent PMSG injection or non-hormonal alternative methods (short dam-litter separation, changing nursing method or lighting programs) are recommended for this reason.

• Animal cells and systems
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• 제13권1호
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• pp.71-78
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• 2009

To clarify the reproductive function of vibration signals in Hynobius, which has externally fertilized eggs, we quantitatively analyzed the body and tail undulations of male Korean salamanders (Hynobius leechii) in sixteen mating events. One large and one small male, and one female were used in each mating event. We analyzed behaviors recorded over a total of 3 hrs for each mating event; 2 hrs before and 1 hr after female's oviposition. Males touched females using their snouts or body trunk throughout the entire mating periods, but females touched males increasingly more after approximately 1 hr before oviposition. Males conducted body undulations more than 50 times per 10 minutes at a mean frequency of 0.64 Hz. Large males conducted more body undulations than small males, particularly on the tree twig where females attached their egg sacs. Males responded to other males' body undulation throughout the mating period by orienting their head towards, approaching, and touching the undulating male. Females only responded for about 10-20 min before ovipositing, and most responses were directed to the large male's body undulation. Males conducted tail undulations 3.0 times per 10 min at a mean frequency of 1.7 Hz and most tail undulations occurred after one male bit the other male. These results suggest that body undulations function in both male-female and male-male interactions, while tail undulations mainly functions in male-male competition. Also, male H. leechii appear to actively attract females, while females respond to the males only at times close to oviposition.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.1-7
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• 2008

In this minireview we focus on how males may exploit female's sensitivity to predation risk in the context of mating. It has been shown in studies on guppies and jumping spiders that in response to altered female behaviors, which are adaptations to the unfavorable environment and a consequence of females' higher sensitivity to predator's presence as well as females' higher predation risk, males can adopt condition-dependent mating tactics. It appears that in such cases males do not modify their reproductive behavior directly in response to their own perception of predation risk, but indirectly in response to changes in female behavior induced by predator presence. It has also been recently shown in crabs that males can exploit female behavior by creating safer habitat spots, which increases the male mating success. Hence all the evidence suggests that males not only respond to female sensitivity to the natural variation in predation risk, but that males can also exploit female behavior by altering the environment. As a logical extension of these findings, we present a hypothesis that in certain conditions males can manipulate the environment in order to increase the predation risk and to induce female behaviors that enhance the male's mating success with the increased predation risk. We propose that such a manipulation to increase predation risk is expected to evolve in males of species with a strong sexual conflict and female-biased predation risk. Although empirical evidence has not been yet shown, initial observations in a water strider species in Korea, Gerris gracilicornis, seem to support this hypothesis.