캐비어에 대한 수요가 증가하면서 캐비어 종류의 진위 여부를 확인 할 수 있는 분석법 마련이 필요해졌다. 본 연 구에서는 캐비어 종류을 나누는 철갑상어 종 특이 KASP 마커를 개발하였고 모니터링을 통해 국내 유통중인 불법 캐비어 제품을 확인하고자 하였다. 본 연구에서는 16S ribosomal RNA gene, cytochrome b gene, cytochrome c oxidase subunit I gene, cytochrome c oxidase subunit II gene, NADH dehydrogenase subunit 5 gene에서 철갑상어 종 특이적인 SNP를 선정하고 이를 표적하는 KASP 마커 11종을 개발하였다. 개발한 KASP 마커를 이용하여 한국 의 온라인 마켓에서 유통중인 캐비어 10종을 모니터링 분 석한 결과 2개의 제품에서 제품에 표기된 철갑상어 종과 다른 것으로 확인하였으며 두 제품 모두 실제보다 더 비 싼 캐비어로 둔갑하여 판매한 것으로 확인되었다. 본 연 구를 통해 제작한 KASP 분석방법으로 유통되는 캐비어 종류 분류가 가능하였고 모니터링을 통해 국내 유통되고 있는 불법 캐비어 제품도 확인하였다. 이에 따라 본 연구 에서 개발한 SNP기반 KASP 분석법으로 불법 캐비어 제 품 유통 근절에 기여 할 수 있을 것으로 기대한다.
Changes of gonadal morphology and mRNA expression patterns of vitellogenin were investigated in Siberian sturgeon Acipenser baerii (Chondrostei) during its early gonadal maturation period. Early differentiations and morphological transitions of both ovaries and testes appeared to occur actively until the age of 3 years, however from then on, the maturation patterns to full maturity were largely gender-dependent, in which males showed a faster progression of maturation than did females while females experienced a steady-state progress with a lagged interval before entering the final maturation. Expression of vitellogenin mRNAs are closely correlated with transitional patterns of gonadal appearances. In both females and males, hepatic mRNA levels of vitellogenin exponentially increased in the earliest interval (up to 1-year-old). However, in subsequent periods, vitellogenin expression in females continued to increase with age, whereas in males, the expression stabilized at a younger age. Nevertheless, at the age older than or equal to 7-year-old, fully matured individuals showed a quite low level of vitellogenin expression in both females and males. Collectively, results from this study could be useful as a fundamental guideline to address the gonad maturation of this sturgeon species, which is helpful for making practical decisions about farming practices and management for caviar production on local sturgeon farms.
Behavioral response to a diel photoperiodicity (500 lx for 16 h, 5 lx for 4 h and < 0.5 lx for 4 h) and phototactic characteristics in dark conditions were examined with Siberian sturgeon Acipenser baerii (Chondrostei, Actinopterygii) prelarvae. Siberian sturgeon prelarvae represented both qualitative and quantitative changes in their behavioral patterns according to different light intensities in a diel photoperiodicity. Under daylight conditions (500 lx), prelarvae displayed saltatory changes of behavioral features with ages (Day 0-Day 9) in a general order of swimming-up/drifting, swimming in the upper water column, benthic swimming with rheotaxis, schooling and postschooling behavior. Compared to daylight conditions, prelarvae tended to show more benthic performances and quantitative reductions of schooling and postschooling behaviors under dimlight conditions (5 lx). Under dark conditions (< 0.5 lx), prelarvae exhibited a fairly uniform behavioral pattern characterized by the benthic swimming across the bottom of the tank. From phototaxis tests under dark conditions, navigational responses of prelarvae to a spotlight illumination were quantitatively changed as their ages increased. The phototactic responses reached the peak on Day 2, continued until Day 4, and then gradually decreased until Day 8. A partial recovery of positive phototaxis was observed on Day 9. Data from this study suggest that the diel light cycle as well as the light intensity of each interval in the cycle should be considered as important components of a practical guide for evaluating fitness and developmental states of artificially propagated Siberian sturgeon prelarvae.
Somatic cell nuclear transfer (SCNT) and induced pluripotent stem cell (iPS) experiments have generally demonstrated that a differentiated cell directly converts into a undifferentiated or pluripotent state. In SCNT experiment, nuclear reprogramming is induced by exposure of introduced donor cell nuclei to the recipient cytoplasm of matured oocytes. Although nuclear reprogramming of cells by the ex-ovo methods is not always consistent or efficient, it has been suggested that a combination of nuclear reprogramming technique may improve the efficiency or frequency of normal development of SCNT embryos. Here we hypothesized that treatment of somatic cells with extracts prepared from GV stage sturgeon's oocytes prior to their use as nuclear donors for SCNT will improve subsequent development. We reported a reversible permeabilization protocol with digitonin to deliver sturgeon oocyte exteact (SOE) to porcine fetal fibroblast cell nuclei ex ovo. Porcine fibroblasts were permeabilized by 4 μg/ml of digitonin for 2 min at 4℃ and then incubated in SOE for 7h at 15 18℃ followed by resealing of cell membrane. As results, no difference was observed in the number of fused couplets or the number of fused couplets that cleaved between the extract treated or control group. However, there was a significantly decrease in the percentage of fused couplets that developed to the blastocyst stage in the SOE treated group (p<0.05). Histone acetylation status was determined using an antibody to acetylation at lysine 9 on histone 3 (H3K9Ac). The intensity of H3K9Ac staining in 1-cell stage NT embryos was significantly increased when treated with the SOE (p<0.05), similar to that in 1-cell stage IVF embryos. In addition, porcine NT embryos reconstructed by using donor cell exposed to SOE prior to cell fusion significantly decreased developmental competence to the blastocyst stage but increased pluripotent gene expressions (Sox2, Nanog and Oct3/4) when compared with those in normal NT embryos (p<0.05).
본 연구에서는 양식어종으로 매우 부가가치가 높은 철갑상어의 영양성분 분석과 중간수분식품 개발을 위해 건조시 온도와 당 및 염 침지 조건에 따른 품질특성을 조사하였다. 철갑상어의 일반성분은 수분 73.2%, 단백질 19.9%, 지방 5.7%, 회분 1.1% 및 가용성 무질소물 0.1%였으며, 주요 무기성분으로는 K, P 및 Mg 으로 그 함량은 각각 317.70 mg/100 g, 259.88 mg/100 g 및 29.78 mg/100 g 순이었다.