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31.
Callus production from willow (Salix viminalis L.) protoplasts 总被引:2,自引:0,他引:2
Protoplasts were isolated from cell suspensions of Salix viminalis (basket willow) clone 78-0-90 and S. schwerinii clone 77-0-77, using cellulysin and macerase in modified Woody Plant medium. For clone 78-0-90, 6.3 · 106 ± 1.9 · 106 protoplasts were obtained per gram fresh weight. Cell divisions started two days after protoplast isolation and gave rise to callus which has been maintained in culture for up to four years. Protoplast yield from the clone 77-0-77 was lower (less than 106 protoplasts per gram cells), cell division was infrequent and no callus was obtained. Protoplasts were also isolated from the leaves of willow shoot cultures using cellulysin and pectolyase, but these did not show cell divisions.Abbreviations BA
benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- MS medium
Murashige & Skoog (1962) medium
- WP medium
Woody Plant medium (Lloyd & McCown 1981) 相似文献
32.
Sylvia Waara Anita Wallin Agneta Ottosson Tage Eriksson 《Plant Cell, Tissue and Organ Culture》1991,27(3):257-265
A culture protocol has been developed for mesophyll protoplasts isolated from various dihaploid clones of potato. A special effort was made to promote the growth of initially dividing cells to form cell colonies and calli. An increase in plating efficiency in 3 different dihaploid clones and one doubled dihaploid clone was obtained after serial dilution of cultures with a suitable amount and type of medium at different stages of cell colony development. Plating on a refined semi-solid medium after 14 days of culture further improved both the yield and the quality of calli obtained. The refined plating medium also enhanced shoot regeneration ability from 67 to 90% in one of the dihaploid clones (67:9). The refined culture protocol could also be used without causing a decrease in plating efficiency at a low population density adjusted after 3 days of culture. The ploidy level of plants regenerated from dihaploid protoplasts were determined by chromosome counting and DNA analysis by flow cytometry. Most of the plants were aneuploid or tetraploid although, some dihaploid plants were obtained after protoplast culture of 2 dihaploid clones derived from the same cultivar (cv. Stina).Abbreviations BA
benzyladenine
- 2,4-D
dichlorophenoxyacetic acid
- GA3
gibberellic acid
- NAA
naphthaleneacetic acid 相似文献
33.
Abstract: The L-[3 H]glutamic acid binding capability of rat cerebellar membranes prepared with or without preincubation at 37°C followed by washing was investigated. The two preparations ( KD = 820 nM, Bmax = 54.5 pmol/mg protein; KD = 509 nM, Bmax =13.0 pmol/mg protein) showed no difference in specificity of the binding of the ibotenic acid analogues, consistent with the removal of an endogenous inhibitor by the preincubation at 37°C followed by washing. The order of potency of the ibotenic acid analogues as inhibitors of L-[3 H]glutamic acid binding is different from the order of potency in vivo , suggesting that the binding sites found are different from the physiological glutamic acid receptor. 相似文献
34.
Explants fromPisum sativum shoot cultures and epicotyls were transformed by cocultivation withAgrobacterium tumefaciens vectors carrying plant selectable markers and transformants could be selected on a medium containing kanamycin. Transformants could also be obtained at a low frequency by cocultivating small protoplast-derived colonies. The transformed nature of the calli obtained from selection was confirmed by opine assay and DNA analysis. In addition five cultivars of pea were tested for their response to seven differentAgrobacterium tumefaciens strains. The response pattern coincided largely between the different pea cultivars, being more dependent on the bacterial strain than the cultivar used.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- BA
6-benzyladenine
- Km
kanamycin
- NAA
-naphthaleneacetic acid
- NOS
nopaline synthase
- NPT
neomycin phosphotransferase
- OCS
octopine synthase 相似文献
35.
Rafael Tage Biaggio Ronivaldo Rodrigues da Silva Nathalia Gonsales da Rosa Rodrigo Simões Ribeiro Leite Eliane Candiani Arantes Tatiana Pereira de Freitas Cabral 《Preparative biochemistry & biotechnology》2016,46(3):298-304
Peptidases are important because they play a central role in pharmaceutical, food, environmental, and other industrial processes. A serine peptidase from Aspergillus terreus was isolated after two chromatography steps that showed a yield of 15.5%. Its molecular mass was determined to be 43 kD, by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). This peptidase was active between pH 5.0 to 8.0 and had maximum activity at pH 7.0, at 45°C. When exposited with 1 M of urea, the enzyme maintained 100% activity and used azocasein as substrate. The N-terminal (first 15 residues) showed 33% identity with the serine peptidase of Aspergillus clavatus ES1. The kinetics assays showed that subsite S2 did not bind polar basic amino acids (His and Arg) nonpolar acidic amino acids (Asp and Glu). The subsite S1 showed higher catalytic efficiency than the S2 and S3 subsites. 相似文献
36.
Alkaloid biosynthesis in somatic hybrids of Duboisia leichhardtii F. Muell. and Nicotiana tabacum L.
Somatic hybrids of Duboisia leichhardtii and Nicotiana tabacum were obtained by electrofusion followed by individual cloning. The hybrid nature of the cloned cells and regenerated shoots was confirmed by cytological investigation and ribosomal-DNA analysis, respectively. The hybrid plantlets predominantly produced nicotine, while Duboisia plantlets produced both tropane and nicotine alkaloids. Activities involved in tropane-alkaloid biosynthesis were examined in a series of precursor-feeding experiments. The presence in the hybrid plants of activities responsible for the reduction of tropinone, the hydroxylation and epoxidation of hyoscyamine, and the conversion of nicotine to nornicotine demonstrated the presence of the Duboisia genes for these enzyme activities.We thank Mr. T. Shikanai, Kyoto University, for the preparation of rice rRNA. We also appreciate Dr. J.H. Fitchen, Kyoto University, for critical discussion and English correction. 相似文献
37.
Heribert-Nilsson E. Schiemann Tage Ellinger Schleip und Siemens 《Molecular & general genetics : MGG》1920,24(1):98-104
Ohne Zusammenfassung 相似文献
38.
In 123 patients with arterial hypertension the haemoglobin values were determined before and during long-term antihypertensive drug treatment. The haemoglobin values found before treatment did not differ from those found in the normal population. In both sexes the haemoglobin values showed a significant increase after prolonged treatment. In males the average values rose from 15.1 to 16.7 g./100 ml., and in females from 13.96 to 14.82 g./100 ml. The increase in the haemoglobin concentration does not seem to be clearly correlated to the duration of treatment or to the decrease produced in mean blood pressure. On the other hand, the increase in haemoglobin depended to some extent on the nature of treatment. Diuretics alone resulted in a moderate increase only, whereas diuretics in combination with other antihypertensive drugs produced a more pronounced increase in haemoglobin values. 相似文献
39.
Sollid J Rissanen E Tranberg HK Thorstensen T Vuori KA Nikinmaa M Nilsson GE 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2006,176(4):359-369
Hypoxia inducible factor 1 alpha (HIF-1α) initiates expression of a wide variety of genes, some of which are involved in apoptosis
and cell cycle arrest. We have previously shown that crucian carp increases its respiratory surface area 7.5-fold in response
to hypoxia. This change is due to apoptosis and cell cycle arrest in specific parts of its gills. Here we have characterized
crucian carp HIF-1α, and measured mRNA, protein and DNA binding levels during hypoxia exposure in crucian carp gills. We have
also measured an HIF-1α-induced gene, the inducible nitric oxide synthase (iNOS), which has the ability to initiate apoptosis
and cell cycle arrest. Crucian carp HIF-1α was found to have all critical domains known to be important for function. Comparison
of the peptide sequence with other species indicated high similarity with other cyprinid fish, but a pronounced variation
compared to the salmonid, rainbow trout. Further, we found HIF-1α protein to be stabilized during hypoxia. Further, HIF-1α
was often present in normoxia, and showed marked individual weight-dependent variation. We found no alteration of iNOS mRNA
levels during hypoxia exposure. These findings suggest HIF-1α involvement in hypoxia-induced change of respiratory surface
area in crucian carp gills. However, its activity does not seem to be mediated through iNOS. 相似文献
40.