• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.230-235
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• 2009

The effect of auxin transport inhibitor (TIBA and PCIB) or auxin synergist (phloroglucinol) on somatic embryo maturation and germination in Japanese larch (Larix leptolepis) was examined. The addition of 15.8 mg/L ABA+5.0 mg/L PCIB showed most promoted the maturation of cotyledon -staged somatic embryos (177.7/90 mg ESM). In contrast, with treatment of 5.0 mg/L PCIB or 5.0 mg/L TIBA, no somatic embryos were obtained. Considering from this result, PCIB or TIBA alone could not substitute for exogenously supplied ABA for maturation of somatic embryos. In the test of below concentration of 5.0 mg/L PCIB, the highest results were recorded in 15.8 mg/L ABA+2.0 mg/L PCIB (109.3/90 mg ESM) or 15.8 mg/L ABA+5.0 mg/L PCIB (103.7/90 mg ESM). However, 5.0 mg/L phloroglucinol (0/90 mg ESM) or no ABA addition (3/90 mg ESM) had little influence on somatic embryos maturation. In germination study, the highest frequency of plantlet regeneration obtained from the somatic embryos which had matured on 15.8 mg/L ABA+5.0 mg/L PCIB (67.9%). However, either 5.0 mg/L PCIB nor 5.0 mg/L TIBA resulted in obtained from plantlets.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.260-266
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• 2011

An efficient protocol was established for high frequency somatic embryogenesis through a callus culture of Coelogyne cristata. The best frequency of callusing was obtained from a PLB segment (3-5 mm) cultured on MS medium supplemented with coconut water (CW) and a combination of both 3 $mg{\cdot}L^{-1}$ of 2,4-D and BA. When the calli were sub-cultured on the MS medium without any PGRs, the average number of somatic embryos were higher than those with PGRs treatment. NAA is the most critical factor among PGRs, which dramatically hindered for the formation of a somatic embryo. The efficacy of the addition of coconut powder (CP) for somatic embryogenesis was almost the same in all treatments. However, the number of somatic embryos formed distinctly depended on age of the callus. The somatic embryos converted into healthy plants with well-developed shoots on the same medium. Plantlets showed the best responses of root and shoot growth when transferred to $\frac{1}{2}$ MS medium containing 1.5 $g{\cdot}L^{-1}$ of activated charcoal. All plants with above 3.0-cm-high were successfully acclimatized in the greenhouse.

• Journal of Plant Biotechnology
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• v.48 no.1
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• pp.44-53
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• 2021

The present work aims to study the induction of somatic embryogenesis in cork oak (Quercus suber L.) from immature zygotic embryos and young apical leaves obtained from 2-month-old seedlings through acorn germination on sterilized peat. The immature zygotic embryos were grown for 1 month on the mineral solution of MS in the presence of 4.52 µM 2,4-D and 30 g/L sucrose. They were then transferred to the same mineral solution with no added growth regulators. In the third subculture, yellow somatic embryos, characterized by two voluminous cotyledons, were differentiated from the radicle of the immature zygotic embryos. The induction of somatic embryogenesis in young leaves required a series of transfers on different culture media containing 30 g/L sucrose and 100 mg/L myo-inositol. Secondary or recurrent somatic embryogenesis occurred within the immature somatic embryo radicles after 1 month of culture on growth regulator-free medium containing WPM macronutrients, MS micronutrients, and vitamins.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.654-670
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• 2022

Spermatogenesis and testis development are highly structured physiological processes responsible for post-pubertal fertility in stallions. Spermatogenesis comprises spermatocytogenesis, meiosis, and spermiogenesis. Although germ cell degeneration is a continuous process, its effects are more pronounced during spermatocytogenesis and meiosis. The productivity and efficiency of spermatogenesis are directly linked to pubertal development, degenerated germ cell populations, aging, nutrition, and season of the year in stallions. The multiplex interplay of germ cells with somatic cells, endocrine and paracrine factors, growth factors, and signaling molecules contributes to the regulation of spermatogenesis. A cell-tocell communication within the testes of these factors is a fundamental requirement of normal spermatogenesis. A noteworthy development has been made recently on discovering the effects of different somatic cells including Leydig, Sertoli, and peritubular myoid cells on manipulation the fate of spermatogonial stem cells. In this review, we discuss the self-renewal, differentiation, and apoptotic roles of somatic cells and the relationship between somatic and germ cells during normal spermatogenesis. We also summarize the roles of different growth factors, their paracrine/endocrine/autocrine pathways, and the different cytokines associated with spermatogenesis. Furthermore, we highlight important matters for further studies on the regulation of spermatogenesis. This review presents an insight into the mechanism of spermatogenesis, and helpful in developing better understanding of the functions of somatic cells, particularly in stallions and would offer new research goals for developing curative techniques to address infertility/subfertility in stallions.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.51-56
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• 1998

This study was carried out in order to establish plant regeneration via somatic embryogenesis from leaf explant of Ostericum koreanum Kitagawa and to elucidate the effects of NAA and cytokinins (kinetin, BA) on the abnormalities of somatic embryo and the relationship between thecotyledon numberand germinability. Calli were formed on leaf explants cultured on MS agar medium supplemented with various concentrations (0, 0.1, 0.5, 1, 2 mg/L) of NAA and cytokinins. The calli were white, watery and soft, became browning during cultures. Somatic embryos were formed from pale yellowish calli derived browning calli. High frequency somatic embryos were observed on MS medium containing 1 mg/L NAA and 0.1 mg/L BA after 60 days of culture. The mature somatic embryos germinated into plantlets without subculture after 2 weeks. The frequency of normal somatic embryo with two cotyledons was 39.8%. On the other hand, cotyledonary abnormalities of somatic embryos were observed at considerable frequency: 33.6% of somatic embryo with one cotyledon, 15.3% cotyledons with three, 8.2% four cotyledons and 3.1% jar shaped cotyledon. Germination frequency of somatic embryos with two cotyledons was 97.4%, and that of the embryos with abnormal cotyledon was almost similar to that of embryos with two cotyledons, except jar shaped somatic embryos (33.3%).

• Journal of Plant Biology
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• v.39 no.1
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• pp.71-77
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• 1996

Embryogenic callus was selected from callus induced from hypocotyl segment cultures of Daucus carota seedlings on MS basal medium supplemented with 1.0 mg/L 2,4-D. Cell clumps prepared from the embryogenic callus were transferred to MS medium without 2,4-D for somatic embryo development. Cotyledonary abnormalities were frequently observed on somatic embryos developed after the incubation of cell clumps in MS basal medium with 1.0 mg/L 2,4-D for one week and then subculture in the same medium but without 2.4-D for two weeks. The percentage of abnormalities was as follows: 5% one cotyledon, 21% three cotyledons, 6% four cotyledons, 5% five cotyledons, 0.2% six cotyledons and 1% trumpet-like cotyledons. On the other hand, the normal somatic embryo with two cotyledons appeared at 63%. The germination rate of somatic embryos was higher in two cotyledon somatic embryos than in multicotyledonary embryos. Trumpet-like somatic embryos did not germinate normally showing limited elongation and enlargement of roots and cotyledons without shoot development. From anatomical examination circular procambium in the root of somatic embryo began to branch around the middle regions of the hypocotyl which extended into the cotyledons through the cotyledonary nodes and the number of branched procambial strands in hypocotyl was equal to the number of cotyledons. Monocotyledonous somatic embryo always had larger cotyledon than that of somatic embryos with multicotyledons and had horseshoe-like cotyledons where the procambium was of the same structure.ucture.

• Journal of Plant Biotechnology
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• v.6 no.1
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• pp.55-61
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• 2004

Callus induction and somatic embryogenesis are fundamental to cotton tissue culture biotechnology. An efficient protocol for callus induction, somatic embryogenesis and their maturation have been developed to regenerate plantlets from cotton (Gossypium hirsutum L.) variety coker 312. Embryogenic callus was initiated from hypo-cotyl region that was used as an explant at seedling stage when it was about 7-8 days old. Callus induction was achieved through culturing hypocotyls (5-7mm) on $MS_{1a} medium supplemented with 2,4-D (0.1 mg/L) and KT (0.5 mg/L) for six weeks. A friable, colorless, bulky and well proliferating callus becomes greenish with the addition of NAA (2.0 mg/L), ZT (0.1 mg/L) and removal of 2,4-D (M $S_{1b}$) cultured for two weeks then again transferred to $MS_{1a}. 2,4-dichlorophenoxyacetic acid (2,4-D) promoted the proliferation of embryogenic callus, but had a negative effect on the differentiation and germination of somatic embryos. ZT (0.1mg/L) and activated charcoal (2g/L), both hormones play an important role in differentiation and germination of somatic embryos in hypocotyls derived embryogenic callus but in case of cotton, such a capability have been observed on MS medium with 1.92 g/L $KNO_3$, but it is considered to attain somewhat more improvement. High embryogenesis frequency was achieved through nutrient deficient stress treatment. The frequency of globular embryogenesis (two-three folds) was achieved when well proliferating callus was (from $MS_{1a}$ media) cultured on MS (1/5 strength) medium for four weeks. Here the development of anthocyanins is the best indicator for somatic embryogenesis. However, when embryoid callus was cultured on MS (full strength) medium, the globular embryos were developed into normal plantlets immediately. In this procedure 27.49% cotyledenary embryos were developed. Of that 70% cotyledenary embryos were developed not only into normal plantlets but rooted simultaneously, when cultured on MS (with 0.05 mgg/L giberrelic acid) medium. So complete plants could be regenerated through somatic embryogenesis from hypocotyl explants within 6 months.s.

• Korean Journal of Biological Psychiatry
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• v.14 no.4
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• pp.256-261
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• 2007

Objectives : The aim of the present study was to examine whether anxiety and depression of children and mothers were associated with the children's medically unexplained somatic symptoms in attention-deficit/hyperactivity disorder(ADHD). Methods : 83 clinic-referred boys with ADHD and 52 boys without ADHD were included in this study. The frequency of the medically unexplained somatic symptoms, such as general-ache, headache, nausea, eye problems, skin problems, abdominal pain, vomiting was evaluated using the somatic symptom domain of the Child Behavior Checklist(CBCL). Children's anxiety and depression were evaluated using Kovacs Children's Depression Inventory(CDI) and Spielberger's State-Trait Anxiety Inventory(STAI) for children. Maternal anxiety and depression were measured by Spielberger's State-Trait Anxiety Inventory(STAI) and Beck's Depression Inventory(BDI). Stepwise linear regression analysis was used to examine the hypothesis. Results : Score of maternal state anxiety affects the T score of the somatic symptom domain in CBCL significantly(adjusted $R^2$=0.057 ; p=0.026). Conclusion : The frequency of medically unexplained somatic symptom of children perceived by mothers was associated with the high level of maternal state anxiety in ADHD. Frequent maternal report of the children's somatic symptom may be a warrant for the evaluation and management of the maternal state anxiety in ADHD.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.105-110
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• 1995

The experiment were carried out to obtain a somatic hybrid through protoplast fusion between P.hybrid and N. sanderae. The isoenzyme pattern he chromosome number and the phonotype were observed for genetic study on the regenerants obtained from the fusion product cultures. Putative somatic hybrids possessed all the bands that appeared in both mother plane. A specific band was found on the top of the banding pattern which was assumed to be a marker band of somatic hybrid between two genera. Aspartate amninotransferase isoenzyme bands which were found in both mother plane were also revealed in the putative somatic hybrids or deleted in the upper part of H. sanderae band pattern. The chromosome number of P.hybrida was 2n=14, while N, sanderae was 2n=18,but the number of the putative somatic hybrids ranged from n=32 to 36. The phonotype of putative somatic hybrids was intermediate of the mother plants.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.2
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• pp.135-141
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• 2014

The downregulation of A-type $K^+$ channels ($I_A$ channels) accompanying enhanced somatic excitability can mediate epileptogenic conditions in mammalian central nervous system. As $I_A$ channels are dominantly targeted by dendritic and postsynaptic processings during synaptic plasticity, it is presumable that they may act as cellular linkers between synaptic responses and somatic processings under various excitable conditions. In the present study, we electrophysiologically tested if the downregulation of somatic $I_A$ channels was sensitive to synaptic activities in young hippocampal neurons. In primarily cultured hippocampal neurons (DIV 6~9), the peak of $I_A$ recorded by a whole-cell patch was significantly reduced by high KCl or exogenous glutamate treatment to enhance synaptic activities. However, the pretreatment of MK801 to block synaptic NMDA receptors abolished the glutamate-induced reduction of the $I_A$ peak, indicating the necessity of synaptic activation for the reduction of somatic $I_A$. This was again confirmed by glycine treatment, showing a significant reduction of the somatic $I_A$ peak. Additionally, the gating property of $I_A$ channels was also sensitive to the activation of synaptic NMDA receptors, showing the hyperpolarizing shift in inactivation kinetics. These results suggest that synaptic LTP possibly potentiates somatic excitability via downregulating $I_A$ channels in expression and gating kinetics. The consequential changes of somatic excitability following the activity-dependent modulation of synaptic responses may be a series of processings for neuronal functions to determine outputs in memory mechanisms or pathogenic conditions.