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71.
James S. Keddie Eira-Wyn Edwards Terry Gibbons Charles H. Shaw Denis J. Murphy 《Plant molecular biology》1992,19(6):1079-1083
Antibodies raised against purified rapeseed 19 kDa oleosin protein were used to screen an embryo-derived gt11 expression library from Brassica napus. A near full-length cDNA clone, BnV, was isolated. The 781 bp cDNA contained an open reading frame of 549 bp followed by an untranslated region of 222 pb and a poly(A) region of 10 bp. Comparisons between this cDNA and a different oleosin cDNA previously isolated from the same library showed high degrees of sequence similarity in the central domain region and in the 3 untranslated region. Sequence similarities between the derived protein sequence of this cDNA and all other known oleosin protein sequences are discussed. 相似文献
72.
73.
Toshiro Oridate Haruhisa Atsumi Satishi Ito Hajime Araki 《Plant Cell, Tissue and Organ Culture》1992,29(1):27-30
Significant differences in somatic embryogenesis from melon seeds were observed among 18 cultivars; especially, cultivars Earl's Favorite and Barnett which produced a large number of somatic embryos. F1 seeds were obtained by reciprocal crosses between cultivars. Some lines produced a large number of somatic embryos whereas others showed no or poor embryogenic response. Most of the F1 seeds formed somatic embryos. The frequency of somatic embryogenesis decreased as compared to the parents with the highest potential. Transfer of the frequency of somatic embryogenesis from superior responding cultivars to inferior cultivars was proved. It was difficult to determine the mode of inheritance of somatic embryogenesis because there was a large variation in the range of somatic embryogenesis from F2 seeds, and cytoplasmic effect was recognized in certain combinations.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- BAP
6-benzylaminopurine 相似文献
74.
A segment of rye chromosome 1 enhances growth and embryogenesis of calli derived from immature embryos of wheat 总被引:2,自引:0,他引:2
Summary The influence of the short arm of rye chromosome 1 (1RS) from Secale cereale var. Imperial on the growth and differentiation of callus cultures from wheat Triticum aestivum var. Chinese Spring immature embryos was analysed. This chromosome arm was found to stimulate both embryogenesis and the rate of growth of calli. Recombinant lines carrying segments of 1RS were used to delineate the regions of 1RS responsible for the tissue culture effects. The enhancement of embryogenesis and the stimulation of growth were shown to be associated with two distinct genetic regions of the chromosome arm; the former is located between the centromere and the Sec 1 locus, while the latter is situated in the immediate vicinity of the Sec 1 locus. 相似文献
75.
Angie Rizzino Victor Terranova David Rohrbach Craig Crowley Heather Rizzino 《Journal of cellular biochemistry》1980,13(2):243-253
In this paper we have examined the growth and differentiation of the embryonal carcinoma cell line, F9, in the defined medium EM-3 at low density. We show that the growth of F9 and their differentiated cells (F9-diff) in EM-3 is strongly density dependent. At low cell densities the growth of both cell types is severely limited and most of the cells do not survive. Although this poses a problem for working with F9 and F9-diff in EM-3, it provides a convenient assay for identifying molecules that support their growth at low density. Using this assay, we have determined that laminin, a newly isolated glycoprotein of basement membranes, significantly improves the growth and short-term survival of both F9 and F9-diff. However, addition of laminin to EM-3 is insufficient to promote the clonal growth of these cell types. Our findings also indicate that laminin promotes the attachment of F9 and F9-diff in defined media. On the basis of our results, we propose an attachment function for laminin during the early stages of mammalian development. 相似文献
76.
Jürgen Büning 《Development genes and evolution》1980,188(3):215-224
Summary
Bruchidius embryos are shown to be well suited for biochemical studies during early embryogenesis. Mass cultivation is easy, and highly synchronized embryos can be obtained in large numbers (104–105 eggs). A method for in vivo incubation is described which allows the labelling of newly synthesized RNA. The kinetics of3H-ruidine uptake, phosphorylation and incorporation into RNA are presented. By autoradiography, the distribution of newly synthesized RNA is shown. Thereby, stage-specific differences were found in the labelling pattern of vitellophage nuclei, of blastoderm nuclei and of the nuclei of pole cells. The labelling of the cytoplasm remains weak until cellular blastoderm is formed. During late blastoderm and at gastrulation this label increases markedly. Gel electrophoresis of isolated RNA shows that at cellular blastoderm formation most of the label occurs in a region between 18 S and 7 S. Later on, at the onset of gastrulation, the3H-uridine incorporation found in isolated RNA is raised about 10 fold and rRNA synthesis becomes prominent. In a chase experiment, the processing of precursor RNA molecules into shorter RNA species, especially into mature rRNA and 5S RNA, is shown. The advantages of theBruchidius embryo for the biochemical analysis of early RNA synthesis and the regulation of rRNA synthesis in insect embryos are discussed.Dedicated to Professor Dr. Dr. h. c. Bernhard Rensch at the occasion of his 80th birthday 相似文献
77.
Cells of carrot (Daucus carota var. Rote Riesen) were cultured on media inductive and non-inductive for embryogenesis and analyzed for differences in their chromosomal proteins and chromatin template activity. Non-histone proteins were prepared from dehistonized chromatin and their properties were investigated. Non-histone proteins proved to be acidic and associated easily with calf thymus histone. Non-histone proteins were able to counteract the inhibitory effect of histone on DNA-directed RNA synthesis in vitro. Almost the same rate of restoration occurred regardless of the interaction between DNA and protein, when sufficient amounts of non-histone proteins were added. However, once the histone-DNA complex was established, the restoration by non-histone proteins at comparably lower concentration was poor. Another acidic protein, bovine serum albumin, had no effect on histone inhibited RNA synthesis. Also non-histone proteins enhanced the chromatin directed RNA synthesis more than 100%. The template activity of chromatin changed after the inductive treatment of embryo formation and induced cells showed higher template activity than non-indiiced controls after embryo cells were formed. Histone components were the same in inductive and non-inductive cells. On the other hand, there was a correlation between template activity and the stimulation by non-histone proteins of histone-inhibited RNA synthesis. 相似文献
78.
W. C. Chang Y. I. Hsing 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,57(3):133-135
Summary Callus culture was initiated from expiants of mature root tissues of ginseng (Panax ginseng C.A. Meyer) on MS medium enriched with 2,4-D. The ageing callus produced numerous embryoids in this medium. Reculture of these embryoids in media (1/2 MS or B5) supplemented with benzyladenine and gibberellic acid resulted in profuse plantlet regeneration. 相似文献
79.
80.
Summary Two sugarbeet (Beta vulgaris L.) genotypes, REL-1 and REL-2, were used to measure the level of somatic embryo and shoot production from hormone-autonomous
callus plated under varied nutrient medium combinations of abscisic acid with the growth regulators 6-benzyladenine, 1-naphthaleneacetic
acid, or 2,4-dichlorophenoxyacetic acid, with eight sole nitrogen sources, or with different sucrose concentrations. Clone
REL-2 produced embryos up to 35-fold more frequently than clone REL-1. Inclusion of abscisic acid at some concentrations consistently
improved embryo production in all experiments and was observed to stimulate shoot production. At some concentrations, 1-naphthaleneacetic
acid as well as urea and glutamine stimulated greater embryo production over the control, but only for REL-1, for which there
was greater room for improvement. Three and five percent sucrose were superior to 1, 7, and 9%. Higher initial 6-benzyladenine
concentration [in the range 0, 0.1−1.0 mg/L (0.44−4.44 μM)] was associated with lower embryo production but greater shoot regeneration for both clones. REL-2 was significantly better
than REL-1 in shoot regeneration. The range of embryo production was more than 35-fold between genotypes, whereas the range
of physiological effects was no greater than 10-fold. REL-2 has been released to sugarbeet researchers because of its superior
embryogenic and shoot regeneration abilities for application in biotechnology. 相似文献