• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.232-241
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• 1984

A series of experiments were carried out to know the effects of pollen stage, cold shock temperature and duration, and media for callus and green plant induction in rice anther culture. The results indicated that: (a) uninucleate stage of pollen was the most suitable stage for effective callus induction, (b) cold shock temperature of 8$^{\circ}C$ and 12$^{\circ}C$ was appeared to be proper temperature for callus induction, (c) callus induction rate was increased in the eight to 12 days long cold storage, (d) the medium N6 was better than that of N6D for callus induction, (e) green plant induction was better in both 4$^{\circ}C$ and 8$^{\circ}C$ than that of 12$^{\circ}C$ cold shock, (f) green plant frequency was higher in eight to 12 days long cold storage and (g) green plant frequency was doubled in the MS medium when compared with N6 medium.

• Journal of Aquaculture
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• v.13 no.4
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• pp.359-362
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• 2000

Mitotic gynogenesis was induced in the far eastern catfish, Silurus asotus using UV-irradiated heterospecific sperm and cold shock treatment. Eggs were activated with the sperm of mud loach, Misgurnus mizolepis which has been irradiated with UV at dose of 9,000 ergs/$mm^2$. To determine the optimum duration required to prevent the first cleavage, a cold shock at 4$^{\circ}C$ with duration of 20, 30 or 40 min was applied to the eggs 50 min after activation. To induce diploidization of mitogenesis, the most effective protocol was to apply cold shock to 50-min old (after activation) eggs at 4$^{\Circ}C$ for 30min.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.369-373
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• 2003

In spite of potential benefits of anther culture, low productivity of plant regeneration in some genotypes; e.g. tonsil and indica rice, is one of the major obstacles for practical use of anther culture. This study was conducted to improve cold shock method and carbohydrate source for increasing the efficiency of anther culture in rice. The most common carbon source, sucrose was replaced to maltose, which has two molecules of glucose. Maltose increased callus induction 1.4-to 1.8-fold higher in japonica rice, 3.2-to 11.6-fold in tongil types and 2.7-fold in indica rice IR50. Callus induction was increased from 0.2％ to 12.5％ in maltose medium compared to the medium supplemented with sucrose plus glucose in indica rice "Tetep". A simple procedure of vacuum packaging of panicles during cold shock treatment prolonged not only anther viability more than 15 days but also increased callus induction more than 2-fold compared to open-air storage (conventional method). Combining of above two methods, callus induction was increased 28 to 56％ in japonica, 13 to 33％ in tonsil type and 12 to 31％ in indica rice. Plant regeneration was increased 14 to 35％ in japonica, 10 to 20％ in tonsil and 4 to 15％ in indica rice, respectively.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.289-294
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• 2011

We investigated the cold shock sensitivity of DEAD-box RNA helicase gene deleted strains of in Bacillus subtilis CU1065. To understand cold shock effects, cells were cultivated at $37^{\circ}C$ to log phase ($O.D_{600}$=0.5-0.6) and then temperature was shifted to $15^{\circ}C$. Cold shock slow down the growth rate of wild type and deleted strains of DEAD-box RNA helicase gene (ydbR, yfmL, yqfR, deaD). The growth rate of ydbR deleted strain is 5 times severely reduced compared to that of wild type strain (CU1065). But the growth rate of other three (yfmL, yqfR, deaD) deleted strains is nearly equal to the growth rate of wild type. Compared to $37^{\circ}C$, the amount of ydbR and yqfR mRNA transcripts are increased at the growth temperature of $15^{\circ}C$. On the other hands the mRNA transcripts of yfmL and deaD are not changed at both conditions of $37^{\circ}C$ and $15^{\circ}C$. Upon cold shock treatment ydbR mRNA transcript is clearly increased. After treatment of rifampicin (bacteria transcription inhibitor) the amount of ydbR mRNA was measured. Temperature shift from $37^{\circ}C$ to $15^{\circ}C$ and rifampicin treatment showed slowly decay of ydbR mRNA. But at $37^{\circ}C$ and rifampicin treatment ydbR mRNA is rapidly reduced. These results showed that cold shock induction of ydbR mRNA resulted from the stability of ydbR mRNA and not from the transcription induction of ydbR. In relation to these results, we found the cold box element of csp (cold shock protein gene) in 5' untranslated region of ydbR gene. Cold shock induction of ydbR is caused by the stability of ydbR mRNA like the stability of csp mRNA.

• KSBB Journal
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• v.30 no.6
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• pp.345-349
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• 2015

Antifreeze proteins (AFP) inhibit growth and recrystallization of ice, and permit organisms to survive in cold environments. The AFP from an Antarctic bacterium, Flavobacterium frigoris PS1, FfIBP (Flavobacterium frigoris icebinding protein), was produced in E. coli using a cold shock induction system. The culture temperature was shifted from $37^{\circ}C$ to $15^{\circ}C$ and a 20 L culture scale was used. The final weights of dried cell and FfIBP were estimated to be 126 g and 8.4 g, respectively. The thermal hysteresis (TH) activity ($1.53^{\circ}C$) of the produced FfIBP was 3.6-fold higher than that of the LeIBP (Leucosporidium ice-binding protein) produced in Picha. The current study demonstrates that large-scale production of FfIBP was successful and the result could be extended to further application studies using recombinant AFPs.

• Journal of Aquaculture
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• v.8 no.3
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• pp.159-170
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• 1995

Triploid abalone, Haliotis discus hannai, was induced by the cold $(0^{\circ}C\;and\;3^{\circ}C)$ or the heat $(35^{\circ}C\;and\;40^{\circ}C)$ shock procedure with fertilized eggs, 12 min. or 32 min. post fertilization with the various time intervals of shock duration. Fertilization rate of each experimental group was not significantly different from that of corresponding diploid control (P>0.05). However hatching rates and normality rates of triploid larvae were significantly different from those of corresponding diploid control (P <0.05). In heat shock groups at $40^{\circ}C$, fertilization rate of eggs was extremely low $(0\~2.7\%)$ and hatched larvae were not detected in these treatment groups. Incidence of triploidy was confirmed by chromosome count and the highest rates of triploid $(84.0\%)$ revealed in cold $(3^{\circ}C)$ shock with 15 min. treatment duration 12 min. after fertilization. The number of diploid chromosome was 2n: 36, and that of tiploid was 3n=54.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.461-465
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• 2006

We investigated the protein productivity of the promoters for genes showing prolonged induction upon cold shock in Escherichia coli. Six low temperature inducible genes (frdA, glpB, hypB, katG, nupG, ompT) were selected based on the previously reported cDNA microarray based global transcription profiling of Escherichia coli Kl2 in response to cold shock. Their promoter regions were isolated from the genomic DNA of E. coli JM109 and expression levels induced by the promoters were examined by using green fluorescence protein (GFP) as a reporter at $15^{\circ}C$ and $37^{\circ}C$. Among the six promoters, the promoter for nupG showed the highest and prolonged expression at both temperatures and the cold inducibility of nupG promoter was not observed.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.63-68
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• 1970

The induction of polyhedroses in the silkworm, Bambyx mari L., was investigated treating the 5th instar larvae just after eodysis with high temperature (hot water bath at 40$^{\circ}C$ for 5 minutes or dry heat shock at 40$^{\circ}C$ for 30 minutes) and low temperature (5$^{\circ}C$ for 24 hours). The results obtained were as follows; 1. Comparing between the frequency of nuclear and cytoplasmic polyhedroses induced by cold and heat treatments (hot water bath at 40$^{\circ}C$ for 5 minutes), the induction ratio of the former is clearly less than that of the latter. But if the larvae tested with cold were left at room temperature (25$^{\circ}C$) for 30-120 minutes till the next hot water bath (40$^{\circ}C$) for 5 minutes and water bath (20$^{\circ}C$) for 5 minutes, treatments, the frequency of induced cytoplasmic polyhedrosis was more than that in the case of cold or hot water bath treatment alone. 2. The frequency of nuclear and cytoplasmic polyhedrosis induced by cold and successive heat (dry heat shock at 40$^{\circ}C$ for 30 minutes), left at room temperature (25$^{\circ}C$) ti11 the second treatment, the frequency of nuclear polyhedrosis was less than that of cytoplasmic polyhedrosis. 3. The reaction of nuclear polyhedra to stains also differs sharply from that of the cytoplasmic type. In a smear of nuclear polyhedra on a slide staining with Giemsa solution remains unstained against a stained back ground, in contrast to this, the cytoplasmic polyhedra take up stain readly.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1071-1074
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• 2004

The effect of preadaptation at low temperature on cryoprotection was studied for Lactobacillus paraplantarum C7, a bacteriocin producer isolated from kimchi. L paraplantarum C7 cells in their log growth phase were incubated at $15^\circ{C}$, $10^\circ{C}$, or $5^\circ{C}$ for 2, 4, and 6 h, respectively, before being frozen at $-70^\circ{C}$. After 24 h of freezing, viable cells were counted after brief thawing. The freezing-thawing cycles were repeated three more times. Cells preadapted at $10^\circ{C}$ or $5^\circ{C}$ before freezing survived better than control cells, but preadaptation at $15^\circ{C}$ did not confer cryoprotection. Chloramphenicol addition did not destroy the cryoprotection, indicating that protein synthesis was not required for the development of cryoprotection. SDS-PAGE showed induction of a 6.5-kDa protein, a major cold-shock protein, in preadapted cells.

• Journal of Aquaculture
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• v.6 no.4
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• pp.285-293
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• 1993

Gynogenetic diploid of olive flounder, Paralichthys olivaceus were induced by cold shock to fertilized eggs with red sea bream, Paragus major sperm that had been genetically inactivated with 4,800 ergs/$mm^2$ ultraviolet (UV) rays. Cold shock to the eggs at $2^{\circ}C$ for 45 minutes proved to be optimum condition to retain the second polar body. At this treatment, hatching rates of normal fry obtained were more than $33.8\%$. No different growth rates were observed up to 200 days after hatching between control and gynogenetic diploid offsprings. However, body weights of gynogenetic diploids were significantly heavier than that of control 300 days after hatching (p> 0.05). A proportion of female in gynogenetic diploid was significantly higher than that in the control (p< 0.01).