• 한국양식학회지
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• 제12권3호
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• pp.167-173
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• 1999

Blocking the 1st mitotic cleavage was performed in mud loach (Misgurmus mizolepis) using UV-irradiated cyprinid loach (M. anguillicaudatus) sperm and ternal shocks Optimum UV range for inactivation of cyprinid loach sperm and thermal shocks. Optimum UV range for inactivation of cyprinid loach sperm was between 3,150 to 4,050 ergs/m$m^2$. Heat shock treatment ($41^{\circ}C$ for 3mins) with various treatment initiation times ranged from 22 to 50 min post insemination resulted wide range of success for induced gynogenesis. Best result was obtained when haploid egges were shocked at 28 min after insemination (corresponding to metaphase division of the 1st cleavage); 26% of total eggs inseminated were viable diploid gynogens. The hatching success and early survival of the both meiotic and mitotic gynogenetic groups were significantly lower than those of control crosses (P<0.05). Maternal origin of induced gynogenetic mud loach was verified by multi-locus DNA fingerprinting.

• 한국어류학회지
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• 제24권1호
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• pp.1-10
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• 2012

미꾸라지, 미꾸리 및 상반교배를 통해 유도된 종간 잡종의 세포유전학적 분석을 수행하였다. 미꾸라지와 미꾸리의 염색체 수는 각각 2n=48 (12M+4SM+32A), 2n=50 (10M+4SM+36A)이었고, 잡종군들의 염색체수는 각각 2n=49 (11M+4SM+34A)였다. 모든 그룹의 염색체는 동일한 arm number (NF=64)를 갖고 있었으며, 염색체 다형현상, 암수 간 이형의 염색체는 관찰되지 않았다. 적혈구의 크기, DNA 함량을 분석한 결과 잡종군들은 미꾸라지와 미꾸리의 중간 값을 나타냈다. 염색체의 NORs (nucleolar organizing regions)은 모두 동일한 중부염색체 단완부에서 Ag-positive signal이 나타났다. 이상의 결과는 미꾸라지의 1번 중부 염색체와 미꾸리의 차단부 염색체가 Robertsonian 형의 염색체 전좌 과정을 거쳤을 것을 시사한다.

• 한국양식학회지
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• 제10권3호
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• pp.363-371
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• 1997

미꾸리 암컷과 미꾸라지 (Misgurnus mizolepis))$\times$미꾸리(M. anguillicaudatus) 잡종 수컷을 교배시켜 역교배체를 생산하였다. 역교배체의 수정율과 부화율은 친어 수컷으로 사용된 미꾸리와 유사하였다. 더욱이 역교배체는 난황흡수기에 저온에 저항성을 보여 전 실험군이 폐사한 미꾸리군에 비하여 단 14%의 낮은 초기 사망률을 나타내어 뚜렷한 생존율 증가가 관찰되었다. 역교배체의 적혈구 크기와 DNA 함량은 친어 암, 수의 중간을 나타내었고 역교배체는 2n=48 혹은 2n=49인 2가지 종류의 2배체 염색체수를 나타내었다. 부화후부터 6개월 동안 동일 조건에서 성장률을 조사한 결과, 역교배체는 친어 암, 수의 중간 성장을 보여 어류양식시 새로운 양식대상 어종으로의 가능성을 시사하였다. 역교배체는 거의 미꾸리와 체색 및 형태에서 유사하였으나 형질계측결과 친어 암수의 중간을 나타내는 형질 및 몇 개의 새로운 획득형질이 관찰되었다. 역교배체는 부화후 2개월 및 부화후 4개월에서 각기 성비를 조직학적으로 조사한 결과 암컷을 전혀 발견할 수 없어 전 수컷 단성집단 생산의 가능성을 보였다.

• Fisheries and Aquatic Sciences
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• 제17권4호
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• pp.471-478
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• 2014

Genomic organization, including the structural characteristics of 5'-flanking regions of two 65-kDa protein (WAP65) isoform genes associated with warm temperature acclimation, were characterized and their transcriptional responses to immune challenges were examined in the intestine, kidney and spleen of the mud loach (Misgurnus mizolepis; Cypriniformes). Both mud loach Wap65 isoform genes displayed a 10-exon structure that is common to most teleostean Wap65 genes. The two mud loach Wap65 isoforms were predicted to possess various stress- and immune-related transcription factor binding sites in their regulatory regions; however, the predicted motif profiles differed between the two isoforms, and the inflammation-related transcription factor binding motifs, such as NF-${\kappa}B$ and CREBP sites, were more highlighted in the Wap65-2 isoform than the Wap65-1 isoform. The results of qRT-PCR indicated that experimental immune challenges using Edwardsiella tarda, lipopolysaccharide or polyI:C induced the Wap65-2 isoform more than Wap65-1 isoform, although modulation patterns in response to these challenges were tissue- and stimulant-dependent. This study confirms that functional diversification between the two mud loach Wap65 isoforms (i.e., closer involvement of Wap65-2 in the acute phase of inflammation and innate immunity) occurs at the mRNA level in multiple tissues, and suggests that such differential modulation patterns between the two isoforms are related to the different transcription factor binding profiles in their regulatory regions.

• Animal cells and systems
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• 제5권4호
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• pp.303-308
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• 2001

The skin structure of Misgurnus mizolepis was studied based on the microanatomical investigation of skin fragments taken from four regions. The epidermis was distinguished by two types of skin glands, a small mucous cell and a large club cell. The mucous cell was acid sulfomucins (some sialomucins) but the club cell did not give any histochemical tests for mucosubstances. The presence of a well defined lymphatic system with small lymphocytes was established in the stratum germinativum layer of the epidermis. A large number of blood capillaries run very close to each other just below the basement membrane, and a definite area giving AB and PAS positive was present between the basement membrane and scale. These structural features of skin in M. mizolepis seem to be closely related with cutaneous respiration.

• 한국어병학회지
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• 제24권3호
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• pp.269-278
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• 2011

Gene expression of two glyceraldehyde-3-phosphate dehydrogenase (GAPDH) paralogs was examined during Edwardsiella tarda challenge and heavy metal exposures in mud loach (Misgurnus mizolepis; Cypriniformes) kidney and spleen. Transcription of the two mud loach GAPDH paralogs (mlGAPDH-1 and mlGAPDH-2) was significantly modulated by these stimulatory challenges in an isoform-dependent manner. Based on the real-time RT-PCR analysis, the mlGAPDH-2 transcripts were more preferentially induced by E. tarda challenge, whereas the mlGAPDH-1 transcripts were proven to show more inducibility in response to heavy metal exposure using Cd, Cu, Mn and Zn at $5{\mu}M$. Their isoform-specific response patterns were closely in accordance with the TF binding profiles in promoter and intron-1 of the two mlGAPDH isoforms, in which the mlGAPDH-2 has more binding sites for immune-related transcription factors than mlGAPDH-1 while the mlGAPDH-1 possesses exclusively metal responsive elements in its intron. Collectively, the mlGAPDHs are potentially involved in cellular pathways independent of glycolysis and the two GAPDH paralogs might undergo functional diversification or subfunctionalization at least at the transcription level.

• 한국양식학회지
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• 제20권1호
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• pp.65-72
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• 2007

우리나라 주요 담수어종인 미꾸라지(Misgurnus mizolepis)로 부터 apolipoprotein A-I (apoA-I) cDNA를 분리하고 그 구조, 분자 계통 및 발현 특징을 분석하였다. 미꾸라지 apoA-I cDNA는 254개의 아미노산을 암호화하고 있는 762 bp의 ORF를 포함하고 있었으며 아울러 24 bp의 5'UTR 및 293 bp의 3'UTR(종결 코돈 및 poly A tail 제외)를 갖고 있었다. 미꾸라지 apoA-I은 여타 척추동물 apoA-I과의 다중배열 시 염기서열에서는 많은 차이를 나타내었지만 단백질의 구조적 특징은 높은 상동성을 보였고, 또한 척추동물의 apoA-I들과의 분자계통을 분석한 결과, 종래 알려진 분류학적 위치와 비교적 잘 일치하였다. 미꾸라지 apoA-I mRNA는 RT-PCR 분석을 통해 간 및 뇌 조직에서 분석한 다른 조직보다 유의적으로 높게 발현하는 것으로 나타났고, 특히 간에서 가장 높은 발현을 보였다. 수정시부터 부화 후 14일까지 초기 발생 및 치어에서의 apoA-I mRNA 발현을 조사한 결과 수정 8시간째부터 급격한 발현의 증가가 시작되어 이후 지속적으로 높은 발현 수준을 유지하였다.

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.19-28
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• 2000

암컷 미꾸라지, Misgurnus mizolepis와 수컷 미꾸리, M. anguillicaudatus간 잡종과 잡종 3배체를 생산하였으며, 잡종화 및 잡종 3배체화가 망막, 시개 및 trunk kidney에 미치는 영향을 조직학적으로 조사하였다. 잡종은 일부 조직의 핵과 세포 크기에서 양친과 거의 유사하였다. 잡종 3배체는 잡종에 비해 적혈구 세포 및 핵 크기, 망막 내과립층 horizontal cell 핵 크기, 망막신경절 신경세포 층의 신경세포, 시개과립층의 신경세포 핵 및 trunk kidney 2차 근위뇨세관 세포 및 핵 크기에서 증가한 반면 망막 외과립층 수와 2차 근위뇨세관 핵 수에서는 감소하였다. 본 연구 결과 잡종에 비해 잡종 3배체의 일부 조직에서 세포 및 핵 크기 증가를 동반한 세포 수 감소 특성은, 미꾸리류에서의 잡종 및 잡종 3배체의 판별 및 배수화 수준 평가의 한 방편으로 사용 가능할 것이다.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.41-41
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• 2003

Transgenic triploid hybrid between fast-growingtransgenic mud loach (Misgurnus mizolepis) males and cyprinid loach (M. anguillicaudatus) females were generated and their performance on growth, feed conversion ability and reproduction were evaluated. Although the growth accelerations of diploid and triploid transgenic hybrids were not as much as those of original transgenic mud loaches, they still represented persistent growth stimulation ranging 11 to 28 fold when compared to their non-transgenic counterparts, with significantly improved feed conversion efficiency up to 2-fold (compared to non-transgenic hybrid) and 1.5-fold (compared to non-transgenic mud loach) in maximum. The gonad development of diploid hybrids was fertile in histological views regardless of transgenic genotypes but the extent of developmentin hybrid fish were less than mud loach diploids at the same age. On the other hands, very stringent sterility was obtained in both sexes of the triploid hybrid transgenics: ovary and testis from transgenic triploid hybrids were significantly depressed and any notable sign for maturation to ovum or spermatids was not detected. No viable embryo was obtained in a fertilization trial using the suspension prepared from the minced testes of transgenic triploid hybrids. This study may indicate the potential usefulness of triploid hybridization as a mean for reproductive containment of transgenic mud loach.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.112-117
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• 2010

Altered mRNA expression of two metallothionein isoforms (MT-IA and MT-IB) in response to acute heavy metal exposure was examined in mud loach, Misgurnus mizolepis, fry using a real-time RTPCR assay. Sublethal exposure (1 or 5 ${\mu}M$) to Cd, Cr, Fe, Mn, Ni, and Zn resulted in highly variable transcriptional responses of the two MT isoforms to the heavy metal ions, including upregulation, a steady state, and downregulation. Overall, the most potent inducer of both MT isoforms was Cd (up to 6-fold). Another exposure experiment using a series of doses of Cu revealed that the stimulation patterns of the two MT isoforms differed: MT-IA transcription was soon saturated at higher concentrations (about 2-fold at 1-4 ${\mu}M$ of Cu), whereas the activation of MT-IB was more dependent on the treatment dose (increased up to 5-fold at 3 ${\mu}M$). The isoform-specific allotment of constitutive and inducible functions was not as clear in fry as in adult tissues. Coordinated interaction between the MT-IA and MT-IB isoforms was hypothesized based on the finding that MT-IA represented a primary action under 'less stressful' or 'sublethal' conditions, whereas the activation of MT-IB became important under 'more stressful' or 'lethal' circumstances in this species.