대두 체세포배에서 전형성층 분화와 경단분열조직의 발달

최필선,권석윤 한국식물생명공학회 2013 식물생명공학회지 Vol.40 No.1

Immature embryos of Glycine max L. was cultured on Murashige and Skoog’s (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D). After 6 to 8 weeks of culture, immature embryos produced somatic embryos. Of somatic embryos, two cotyledonary embryo (14%), one cotyledonary embryo (37%), fused cotyledonary embryo (43%), and stunted globular embryos (6%) were observed. The procambial strand of cotyledons originated from circular procambial tissues of lower hypocotyl. The circular procambial tissues were independently divided into one or two procambial strand at the edge of cotyledonarynode,and then connected to each cotyledon to form somatic embryos with one or two cotyledons. When cotyledon was a fused type, the circular procambial strand in lower hypocotyl was continuously connected to the cotyledon. Also, somatic embryos with two cotyledons developed a functional shoot apex with the tunica-corpus structure. In contrast, somatic embryos with one or fused cotyledon formed an abnormal shoot apex without the tunica-corpus structure or with non-dome shape in the inter-cotyledonary area. These results indicated that the variation of cotyledon in somatic embryos is closely related to procambial differentiation and shoot apical meristem development.

Dormancy of Somatic Embryos Derived from the Cotyledon of Korean Ginseng

Yang Deok-Chun,Yoon Eui-Soo,Choi Kwang-Tae The Korean Society of Ginseng 1999 Journal of Ginseng Research Vol.23 No.3

발아 직전에 있는 한국인삼의 접합자 배에서 유래된 자엽절편을 이용하여 체세포배를 유도하고 기내 휴면여부를 조사하고자 하였다. 식물호르몬으로써 2,4-D, BAP, kinetin을 첨가하거나 혹은 전혀 식물호르몬이 첨가하지 않은 MS배지에 절편을 배양할 경우 많은 체세포배 혹은 단일배를 획득할 수 있었다. 그러나 이런 배들은 대부분 자엽형 배(cotyledonary stage)까지 발육이 가능하지만 발아가 되지 못하여 더 이상 shoot로 생육되지 못하였고 하얀상태의 자엽형 배로 계속 유지되었다. 그러나 gibberellic acid(1.0 mg/l, $GA_3$)을 처리할 경우 3주 이내에 자엽형 배가 녹색으로 변하면서 발아되었으며, 저온처리($-2^{\circ}C$에서 8주간)를 할 경우에도 체세포배가 정상적으로 발아가 되었다. 체세포배를 $GA_3$및 저온 처리한 후 세포의 구조적변화를 전자현미경으로 관찰한 결과 무처리 체세포배의 자엽내 세포는 발아되지 않은 인삼접합자배의 세포와 같이 지질과립 및 세포질이 농후하며 분화되지 않은 미토콘드리아 및 엽록체를 지녀서 세포의 활성이 약한 휴면 상태의 구조를 가지고 있었다. 그러나 저온처리 및 $GA_3$를 처리한 자엽세포는 지질 및 세포질의 분포가 감소된 반면, 잘 발달된 엽록체와 활성이 강한 미토콘드리아의 구조를 보였다. 따라서 저온 및 $GA_3$처리 후 세포의 대사활동이 활발한 것으로 보아 휴면이 타파된 것으로 판단되었다. Somatic embryos were induced directly from cotyledon explants of Korean ginseng (Panax ginseng C.A. Meyer) on Murashige and Skoog (MS) medium with 2,4-D, BAP, kinetin or lacking growth regulators. When somatic embryos formed on all media grew to cotyledonary stage, the further development of embryos was ceased and remained in white color. By gibberellic acid (over 1.0 mg/1 $GA_3$) treatment, all the somatic embryos turned rapidly to green and germinated within 3 weeks. Chilling treatment also induced the germination of somatic embryos. The effective temperature regime was $-2^{\circ}C$ for over 8 weeks but more higher temperature than $0^{\circ}C$ did not effective for germination of somatic embryos. Ultrastructural observation revealed that the cotyledon cells of somatic embryos without chilling or $GA_3$ treatment contained numerous lipid reserves, dense cytoplasm, proplastids and non-activated mitochondria with poorly differentiated internal structure, but the cotyledon cells of germinating somatic embryos after chilling or $GA_3$ treatment highly vacuolated and contained well-developed chloroplasts and active state of mitochondria enclosing numerous cristae. The above results indicate that in vitro developed somatic embryos of Panax ginseng may be dormant after mature similar to zygotic embryos.

시호(Bupleurum falcatum L) 잎절편으로부터 형성된 체세포배 발생의 형태학적 관찰

조덕이,소웅영 한국식물생명공학회 1995 식물생명공학회지 Vol.22 No.5

시호(Bupleurum falcatum L.)의 잎절편으로부터 체세포배형성을 통한 식물체 재생과 체세포배 발생의 이상을 일으키는 2,4-D의 영향에 대하여 또한 체세포배의 자엽수와 발아와의 관계에 대하여 기술하였다. 배발생능 캘러스는 1mg/L 2,4-D가 첨가된 MS 고형기본배지에서 배양된 캘러스로부터 선발하였다. 2,4-D 첨가 MS 기본배지에서 6주간 배양후 3주간 2,4-D가 제거된 배지에서 배양하여 체세포배 발생과 비정상적인 체세포배의 자엽발생을 관찰하였다. 이상자엽의 빈도는 정상인 2개 자엽에서 65% 인데 비하여 1개의 자엽에서 7%, 3개의 자엽을 갖는 체세포배에서는 25%, 4개 자엽에서는 5%, 5개 자엽에서 2% 및 나팔형 자엽배는 3% 이었다. 2개의 정상적인 자엽을 갖는 체세포배의 발아율이 80%인 것에 비하여 1, 3 4, 5개의 자엽을 갖는 체세포배에서는 25%, 58%, 38% 및 20%로 발아율이 낮았다. 그러나 나팔형의 비정상 체세포배는 전혀 발아되지 않았다. 다자엽배의 구조는 체세포배의 뿌리 또는 배축에서 원통상전형성층을 나타내었지만 자엽절에서는 자엽수와 동일한수의 전형성층속으로 분포되었다. 체세포배의 자엽수 변이는 전형성층의 수와 밀접한 관계가 있다. This study describes plant regeneration from leaf explant of Bupleurum falcatum through somatic embryogenesis, and the effect of 2,4-dichlorophenoxyacetic acid on somatic embryo abnormalities. The relationship between the cotyledon number of somatic embryo and its germinability is also described. Embryogenic calli were selected from calli formed on explants cultured on MS solid basal medium supplemented with 1 mg/L 2,4-D. Cotyledonary abnormalities were observed in somatic embryos which were developed from calli cultured on MS medium with 1 mg/L 2,4-D for 6-week and then subcultured on 2,4-D free MS medium for 3 weeks. The frequency of abnormalities was as follows: 7% of somatic embryos had one cotyledon, 65% of them had two cotyledons, 25% three cotyledons, 5% four cotyledons, 2% five cotyledons, and 3% trumpet-like cotyledons. The two cotyledon somatic embryos were germinated at a frequency of 80%. However the germination frequency of one cotyledon embryo and multicotyledonary embryo was lower than that of the two cotyledon somatic embryo. All of trumper-like somatic embryos did not germinate. Histological observations of multicotyledon embryo showed circular procambium in the root but pocambial strands in the cotyledonary node or upper hypocotyl. The number of the strands was equal to the cotyledon number.

In Vitro Zygotic Embryo Germination and Somatic Embryogenesis through Cotyledonary Explants of Paeonia lactiflora Pall.

Sonali Jana,Iyyakkannu Sivanesan,Mi Young Lim,Byoung Ryong Jeong 한국화훼산업육성협회 2013 화훼연구 Vol.21 No.1

A simple and efficient protocol was developed for somatic embryogenesis from the cotyledon explant of Paeonia lactiflora Pall. Seeds of peony obtained from fieldgrown plants were disinfested and zygotic embryos were excised. For germination, excised embryos were cultured on the Murashige and Skoog (MS) medium supplemented with 3% (w/v) sucrose, 0.8% (w/v) agar, and different concentrations of N6 benzyl-adenine (BA) and gibberellic acid (GA3). The greatest germination percentage (95%) was observed when embryos were cultured on the MS medium with 1.0 mg·L-1 BA and 0.5 mg·L-1 GA3, and maintained at 25 ± 2°C under a 16 h photoperiod. Thirty days old cotyledon explants were cultured on the MS medium supplemented with different concentrations and combinations of plant growth regulators viz., BA, GA3, 2,4-dichlorophenoxyacetic acid (2,4-D), and á-naphthalene acetic acid (NAA). After 90 days, the globular embryos were directly formed on the surface of explants. The highest frequency of somatic embryo induction (72.5) was obtained on the MS medium with 3.0 mg·L-1 BA, 1.0 mg·L-1 NAA, 1.0 mg·L-1 GA3, and 0.1% (w/v) activated charcoal (AC), with a mean number of 14 embryos per explant. Maturation of globular embryos into heart- and torpedo-shape was observed on the same medium. When the torpedo-shaped embryos were transferred onto the same MS medium supplemented with 3.0 mg·L-1 BA, 1.0 mg·L-1 NAA, 1.0 mg·L-1 GA3, and 0.1% (w/v) AC, secondary somatic embryos were observed on the surface of primary somatic embryos. When the embryos were transferred to the MS medium supplemented with 1.0mg·L-1 each of BA and GA3, all of them converted into plantlets, but their growth was very slow.

Callus induction and high-efficiency plant regeneration via somatic embryogenesis in Papaver nudicaule L., an ornamental medicinal plant

Yang, Jing Li,Zhao, Bo,Seong, Eun-Soo,Kim, Myong-Jo,Kang, Won-Hee,Kim, Na-Young,Yu, Chang-Yeon,Li, Cheng Hao The Korean Society of Plant Biotechnology 2010 Plant biotechnology reports Vol.4 No.4

We describe culture conditions for a high-efficiency in vitro regeneration system of Papaver nudicaule through somatic embryogenesis and secondary somatic embryogenesis. The embryogenic callus induction rate was highest when petiole explants were cultured on Murashige and Skoog (MS) medium containing 1.0 mg $1^{-1}$ ${\alpha}$-naphthaleneacetic acid (NAA) and 0.1 mg $1^{-1}$ 6-benzyladenine (BA) (36.7%). When transferred to plant growth regulator (PGR)-free medium, 430 somatic embryos formed asynchronously from 90 mg of embryogenic callus in each 100-ml flask. Early-stage somatic embryos were transferred to MS medium containing 1.0 mg $1^{-1}$ BA and 1.0 mg $1^{-1}$ NAA to germinate at high frequency (97.6%). One-third-strength MS medium with 1.0% sucrose and 1.0 mg $1^{-1}$ $GA_3$ had the highest frequency of plantlet conversion from somatic embryos (91.2%). Over 90% of regenerated plantlets were successfully acclimated in the greenhouse. Secondary somatic embryos were frequently induced directly when the excised hypocotyls of the primary somatic embryos were cultured on MS medium without PGRs. Sucrose concentration significantly affected the induction of secondary embryos. The highest induction rate (89.5) and number of secondary somatic embryos per explant (9.3) were obtained by 1% sucrose. Most secondary embryos (87.2-94.3%) developed into the cotyledonary stage on induction medium. All cotyledonary secondary embryos were converted into plantlets both in liquid and on semisolid 1/3-strength MS medium with 1.0% sucrose.

人參(인삼) 조직배양(組織培養)에 있어 CO2 처리(處理)가 식물체(植物體) 분화(分化) 및 생장(生長)에 미치는 영향(影響)

정찬문,배길관 한국약용작물학회 2000 한국약용작물학회지 Vol.8 No.1

인삼조직배양에서 배양환경 조절방법의 필요성을 검토코자 생장조절물질 IBA, BA, GA 각 3mg/ l 첨가한 MS 배지에 CO2(2500ppm)를 강제 통기방식에 의해 기내에 처리하여 기관분화 유형별로 특성을 조사하였던 바 결과를 요약하면 다음과 같다. 저장종자의 분화능은 저온처리 60일 종자에서 적출한 배에 비하여 80일정도 저온처리한 성숙된 배의 자엽조직이 양호하였다. 기관발생 유형에서 CO2처리 효과는 부정아 형성보다 shoot primordium 의 생장과 발달에 현저한 효과가 있었고 1개의 배로부터 shoot primordium 을 통해 수백 개의 신초분화가 가능하였다. 배발생 유형에서 CO2처리는 무처리에 비해 indirect somatic embryo 분화 모두에 효과가 있었다. Indirect somatic embryo는 대체로 유관속 중심주와 상배축이 미분화된 관계로 신초가 분화 생장하지 못하였다. 그리고 direct somatic embryo는 자엽 이변의 하단부에서 분화 발달하였고 지상부와 지하부 그리고 잠아를 갖는 완전한 식물체로 생장하였다. This experiment was conducted to investigate the effects of length of storage period under low temperature, CO2 enrichment and addition of plant growth regulators in Murashige and Skoog medium on the plant regeneration of Korean ginseng (Panax ginseng C. A. Meyer). Seeds were treated for 60 and 80 days respectively under 5℃ environment. 2500ppm of CO2 was enriched by ventilation. Three plant growth regulators added to the medium were Indolbutyric acid, Benzyladenin and Gibberellic acid (GA3). The result indicated that : The capacity of differentiation was higher in the aged cotyledons from the seeds treated for 80 days under low temperature condition than in those treated for 60 days. CO2 enrichment had stimulating effects on the growth and development of shoot primordium significantly but less effects on the formation of adventitious buds. From one zygotic embryo hundreds of plantlets were differentiated. CO2 enrichment had effects on the formation of both indirect somatic embryo and direct somatic embryo. Indirect somatic embryo showed little growth and differentiation, being undifferentiated vascular stele and epicotyl. Direct somatic embryos were formed on the epidermis of backside basal part of cotyledon. Those embryos developed to whole plant having latent bud.

Comparison of Microtubule Distributions between Somatic Cell Nuclear Transfer and Parthenogenetic Porcine Embryos

Park, Joo-Hee,Kwon, Dae-JinK,Lee, Beom-Ki,Hwang, In-Sun,Park, Choon-Keun,Yang, Boo-Keun,Cheong, Hee-Tae The Korean Society of Animal Reproduction 2009 Reproductive & developmental biology Vol.33 No.1

The aim of this study was to examine the microtubule distributions of somatic cell nuclear transfer (SCNT) and parthenogenetic porcine embryos. Porcine SCNT embryos were produced by fusion of serum-starved fetal fibroblast cells with enucleated oocytes. Reconstituted and mature oocytes were activated by electric pulses combined with 6-dimethlyaminopurine treatment. SCNT and parthenogenetic embryos were cultured in vitro for 6 days. Microtubule assembly of embryos was examined by confocal microscopy 1 hr and 20 hr after fusion or activation, respectively. The proportions of embryos developed to the blastocyst stage were 25.7% and 30.4% in SCNT and parthenogenetic embryos, respectively. The frequency of embryos showing $\beta$-tubulins was 81.8% in parthenogenetic embryos, whereas 31.3% in SCNT embryos 1 hr after activation or fusion. The frequency of the embryos underwent normal mitotic phase was low in SCNT embryos (40.6%) compared to that of parthenogenetic ones (59.7%) 20 hr after fusion or activation (p<0.05). The rate of SCNT embryos with an abnormal mitosis pattern is about twice compared to that of parthenogenetic ones. The spindle assembly and its distribution of SCNT embryos in the first mitotic phase were not different from those of parthenogenetic ones. The result shows that although microtubule distribution of porcine SCNT embryos shortly after fusion is different from parthenogenetic embryos, and the frequency of abnormal mitosis 20 hr after fusion or activation is slightly increased in SCNT embryos, microtubule distributions at the first mitotic phase are similar in both SCNT and parthenogenetic embryos.

Somatic Embryogenesis - Apical Meristems and Embryo Conversion

Yeung, Edward C.,Stasolla, Claudio The Korean Society of Plant Biotechnology 2000 식물생명공학회지 Vol.27 No.4

A large amount of information is currently available for somatic embryogenesis of plants. However, one common problem related to somatic embryos is that the conversion rate can be low for some species. Apical meristems are responsible for post-embryonic growth of the embryo. The low percentage observed is most likely a result of poor apical meristem development or defects in the meristem organization during somatic embryogenesis. In flowering plants, apical meristems are well developed by the late heart stage of zygotic embryo development. In conifers, such as white spruce, apical meristems are formed at the pre-cotyledon stage. Thus, apical meristem development occurs very early, prior to the maturation stage of embryo development. Once formed, meristems are stably determined. In the somatic embryo, as exemplified by white spruce, since embryo development is not synchronous, tissue differentiation including apical meristem formation occurs throughout the“maturation”stage. Different apical meristem organizations can be found among different individuals within a population. In contrast to their zygotic counterparts, the apical meristems appear not to be stably determined as their organization, as the shoot apical meristem especially, can be easily modified or disrupted. Precocious germination seldom results in functional plantlets. All these observations suggest that the conditions for somatic embryo maturation have not been optimized or are not suitable for meristem formation and development. The following strategies could improve meristem development and hence conversion: 1. Simulate in ouuio conditions to promote meristem development prior to the“maturation”treatment.2. Prevent deterioration of apical meristem organization during somatic embryo maturation.3. Promote further meristem development during embryo germination.

Expression of polo-like kinase 1 in pre-implantation stage murine somatic cell nuclear transfer embryos

Moon, Jeonghyeon,Roh, Sangho The Korean Society of Veterinary Science 2019 Journal of Veterinary Science Vol.20 No.1

<P>Somatic cell nuclear transfer (SCNT) has various applications in research, as well as in the medical field and animal husbandry. However, the efficiency of SCNT is low and the accurate mechanism of SCNT in murine embryo development is unreported. In general, the developmental rate of SCNT murine embryos is lower than <I>in vivo</I> counterparts. In previous studies, polo-like kinase 1 (Plk1) was reported to be a crucial element in cell division including centrosome maturation, cytokinesis, and spindle formation. In an initial series of experiments in this study, BI2536, a Plk1 inhibitor, was treated to <I>in vivo</I>-fertilized embryos and the embryos failed to develop beyond the 2-cell stage. This confirmed previous findings that Plk1 is crucial for the first mitotic division of murine embryos. Next, we investigated Plk1's localization and intensity by immunofluorescence analysis. In contrast to normally developed embryos, SCNT murine embryos that failed to develop exhibited two types of Plk1 expressions; a low Plk1 expression pattern and ectopic expression of Plk1. The results show that Plk1 has a critical role in SCNT murine embryos. In conclusion, this study demonstrated that the SCNT murine embryos fail to develop beyond the 2-cell stage, and the embryos show abnormal Plk1 expression patterns, which may one of the main causes of developmental failure of early SCNT murine embryos.</P>

Comparison of Microtubule Distributions between Somatic Cell Nuclear Transfer and Parthenogenetic Porcine Embryos

Joo-Hee Park,Dae-Jin Kwon,Beom-Ki Lee,In-Sun Hwang,Choon-Keun Park,Boo-Keun Yang,Hee-Tae Cheong 한국동물생명공학회(구 한국동물번식학회) 2009 Reproductive & developmental biology Vol.33 No.1

The aim of this study was to examine the microtubule distributions of somatic cell nuclear transfer (SCNT) and parthenogenetic porcine embryos. Porcine SCNT embryos were produced by fusion of serum-starved fetal fibroblast cells with enucleated oocytes. Reconstituted and mature oocytes were activated by electric pulses combined with 6-dimethlyaminopurine treatment. SCNT and parthenogenetic embryos were cultured in vitro for 6 days. Microtubule assembly of embryos was examined by confocal microscopy 1 hr and 20 hr after fusion or activation, respectively. The proportions of embryos developed to the blastocyst stage were 25.7% and 30.4% in SCNT and parthenogenetic embryos, respectively. The frequency of embryos showing β-tubulins was 81.8% in parthenogenetic embryos, whereas 31.3% in SCNT embryos 1 hr after activation or fusion. The frequency of the embryos underwent normal mitotic phase was low in SCNT embryos (40.6%) compared to that of parthenogenetic ones (59.7%) 20 hr after fusion or activation (p<0.05). The rate of SCNT embryos with an abnormal mitosis pattern is about twice compared to that of parthenogenetic ones. The spindle assembly and its distribution of SCNT embryos in the first mitotic phase were not different from those of parthenogenetic ones. The result shows that although microtubule distribution of porcine SCNT embryos shortly after fusion is different from parthenogenetic embryos, and the frequency of abnormal mitosis 20 hr after fusion or activation is slightly increased in SCNT embryos, microtubule distributions at the first mitotic phase are similar in both SCNT and parthenogenetic embryos.