共查询到20条相似文献,搜索用时 93 毫秒
1.
就近年来有关被子植物的离体受精、合子的离体发育以及受精与早期胚胎发育过程中的基因表达的研究情况作了介绍。 相似文献
2.
离体培养下大豆体细胞胚胎发生的组织学研究 总被引:6,自引:0,他引:6
大豆胚状体可以直接从未成熟的子叶表皮及表皮下面1—3层细胞发生。这些细胞经过脱分化后,首先形成细胞质浓厚、核大的胚的发生细胞,胚发生细胞再分裂形成胚性细胞团,胚性细胞团再继续分裂形成胚状体。胚状体的发育过程和合子胚一样,经过球形、心形,鱼雷期和子叶期等诸阶段发育成小植株。此外,在诱导胚状体发生过程中,还观察到另一值得注意的现象:在未成熟胚的子叶表皮下面1至较深处的数层细胞,也转变成分生状细胞团,这些分生状细胞团呈不规则状,从其起源看,可称它们为内生“胚状体”,这些内生“胚状体”培养至20天,即停止生长发育。 相似文献
3.
柑桔胚珠培养中形态发生的扫描电镜观察 总被引:3,自引:0,他引:3
在附加500mg/L酷蛋白水解物的MT培养基上,7-8周龄的Peng柑胚珠可同时产生球形胚状体和胚性愈伤组织。在继代培养中,愈伤组织的形态发生可通过体细胞胚胎发生或发生两条途径同时进行。对正常体细胞胚胎发生。异常体细胞胚胎发生,次生胚胎发生及发生的过程和形态特征进行了系统的扫描电镜观察,并提出了在扫描电镜下鉴别双子叶植物胚状体和不定芽的形态依据。 相似文献
4.
甜樱桃胚胎离体培养 总被引:4,自引:0,他引:4
甜樱桃(Cerasusavium)果实采收后贮藏在40℃下30~40d。除去果肉,将内果皮撬开后,取出胚放在无菌水中浸泡30min,70%乙醇中30s,再用0.2%HgCl2或2%~4%NaOCI表面灭菌20min,最后用无菌水冲洗4次。将胚切成两部分,一部分带有胚珠(大小为整个胚的2/3),另一部分为子叶。将带有胚珠的外植体接种在诱导培养基(MS+0.5ms·*-‘6-BA+2%蔗糖十0.8%琼脂)上,20d后观察统计胚胎发育类型。然后,将外植体发育成的植株切除或保留主根转入增殖培养基(MS+0.5mg·L-‘6-BA+2%蔗糖十0.8%琼脂)。切除主根的试管苗培… 相似文献
5.
6.
玉米芽尖培养中的高频率体细胞胚胎发生与植株再生(简报) 总被引:14,自引:0,他引:14
通过诱导玉米芽尖产生胚性愈伤组织,建立起高频率植株再生的玉米芽尖培养实验体系。在MS+1.0mg·L-16-BA+0.2mg·L-12,4-D+500mg·L-1CH的培养基上诱导愈伤组织并继代培养1次后,将愈伤组织转移到Ms+0.5mg·L-16-BA+0.4mg·L-1IBA+500mg·L-1CH的分化培养基上,可形成大量的体细胞胚胎。组织学观察表明,体细胞胚胎主要发生在胚性愈伤组织表面与表层下部。不同基因型的芽尖形成愈伤组织和再生植株的能力不同。 相似文献
7.
墨兰雌配子体和胚胎发生 总被引:5,自引:1,他引:5
墨兰的胚珠倒生型,具薄珠心和二层珠被。胚囊发育为葱型,成熟胚囊为8核,从传粉型受精约100d,正常双受精。初生胚乳细胞分裂为具2-6个核的胚乳。胚具5-6细胞的胚柄。传粉到种子成熟约8个月,成熟种子只具单层细胞的种皮和一个未分化的球形胚,胚柄及胚乳都消失。 相似文献
8.
9.
火炬松细胞悬浮培养体细胞胚胎发生的研究 总被引:4,自引:0,他引:4
用火炬松成熟合子胚诱导产生的胚性愈伤组织建立了胚性细胞悬浮系。研究了细胞密度,继代时间和ABA浓度等对悬浮条件下胚性柄细胞团及体细胞胚形成的影响。结果表明:当细胞密度为6×10^3个/ml,继代时间为2个月,ABA浓度为5mg/L时,最有利于ESM及SE发生。在悬浮培养条件下,还观察到裂生胚及子叶原基的分化。 相似文献
10.
11.
结球甘蓝游离小孢子胚胎发生 总被引:12,自引:0,他引:12
以结球甘蓝品种“强夏”为材料进行游离小孢子培养,对与胚胎发生关系密切的因子进行探讨。研究结果表明,在盛花前期取材最适宜;单核晚期至双核期的小孢子才能发育成胚状体;含17%蔗糖的培养液在培养初期有利于小孢子存活;培养3d后胚胎诱导则以14%蔗糖浓度为最好;高浓度(17%)蔗糖培养3d后添加低浓度(11%)蔗糖培养液能大大提高胚胎发生能力,比一直在14%蔗糖培养液培养的提高282.4%,比更新培养液培养的提高126.1%。 相似文献
12.
13.
14.
Peptidases in the extracellular space might affect the integrity of recombinant proteins expressed in, and secreted from, plant cells. To identify extracellular peptidases, we recovered the leaf intercellular fluid from Nicotiana tabacum plants by an infiltration-centrifugation method. The activity of various peptidases was detected by an in vitro assay in the presence of specific inhibitors, using BSA and human serum gamma-globulin as substrates. Peptidases were detected by 1- and 2-D zymography in a polyacrylamide gel containing gelatin as substrate. Proteolytic activity was observed over a wide range of molecular masses equal to, or higher than, 45 kDa. To identify the peptidases, the extracellular proteins were digested with trypsin and analyzed by LC and MS. Seventeen peptides showing identity or similarity to predicted plant aspartic, cysteine, and serine peptidases have been identified. The extracellular localization of a cysteine peptidase aleurain homolog was also shown. 相似文献
15.
16.
The stimulation of dicotyledonous leaf growth by light depends on increased H+ efflux, to acidify and loosen the cell walls, and is enhanced by K+ uptake. The role of K+ is generally considered to be osmotic for turgor maintenance. In coleoptiles, auxin‐induced cell elongation and wall acidification depend on K+ uptake through tetraethylammonium (TEA)‐sensitive channels (Claussen et al., Planta 201, 227–234, 1997), and auxin stimulates the expression of inward‐rectifying K+ channels ( Philippar et al. 1999) . The role of K+ in growing, leaf mesophyll cells has been investigated in the present study by measuring the consequences of blocking K+ uptake on several growth‐related processes, including solute accumulation, apoplast acidification, and membrane polarization. The results show that light‐stimulated growth and wall acidification of young tobacco leaves is dependent on K+ uptake. Light‐stimulated growth is enhanced three‐fold over dark levels with increasing external K+, and this effect is blocked by the K+ channel blockers, TEA, Ba++ and Cs+. Incubation in 10 mm TEA reduced light‐stimulated growth and K+ uptake by 85%, and completely inhibited light‐stimulated wall acidification and membrane polarization. Although K+ uptake is significantly reduced in the presence of TEA, solute accumulation is increased. We suggest that the primary role of K+ in light‐stimulated leaf growth is to provide electrical counterbalance to H+ efflux, rather than to contribute to solute accumulation and turgor maintenance. 相似文献
17.
陈静 《武汉生物工程学院学报》2006,(2)
介绍了近年来国际上有关植物体外胚胎发生的最新信息,主要包括合子的分离、融合、培养等技术;其中重点介绍了体外人工合子的发生与培养的技术,该技术不同于通过体内研究技术研究受精和胚胎发生过程中的信号传递。体外研究对于解决体内研究的难题有较大的帮助。 相似文献
18.
Protoplasts isolated from Nicotiana tabacum (L.) leaves were cultured for 6 days in liquid medium and some features of their antioxidant capacity were investigated.
Ascorbate exported into the culture medium was oxidized non-enzymically, whereas important modifications of the enzymic scavenging
activity were detected inside protoplasts. A new pool of isoenzymes, most of them with cytoplasmic characteristics, ensures
the increased ascorbate peroxidase activity. The specific activity of other enzymes involved in the ascorbate/glutathione
cycle, such as dehydroascorbate reductase and glutathione reductase, and of glutathione peroxidase were modified, resulting
in cultured protoplasts with quantitative differences in antioxidant capacity compared to leaves. The hypothesis presented
here suggests that the new scavenging system is related to differences in the compartment-specific accumulation of active
oxygen species following protoplast isolation.
Received: 8 December 1997 / Revision received: 27 March 1998 / Accepted: 10 April 1998 相似文献
19.
Sang-Yoon Lee Yong-Hoon Kim Yun-Sook Roh Hyun-Jong Myoung Ki-Yong Lee Dong-Il Kim 《Enzyme and microbial technology》2004,35(6-7):663-671
The production of hGM-CSF was investigated in both a flask and a 5-l bioreactor, using transgenic Nicotiana tabacum suspension cells. While the maximum cell density and secreted hGM-CSF in the flask were 15.4 g l−1 and 6.5 μg l−1, respectively, those in the bioreactor were 15.6 g l−1 and 7.6 μg l−1. No detectable growth inhibition, shorter production of hGM-CSF and reduced cell viability in the batch bioreactor were observed under the specific conditions used compared with the flask culture. To improve the productivity, a perfusion culture was carried out in the bioreactor, with three different perfusion rates (0.5, 1.0 and 2.0 day−1). In all cases, the hGM-CSF in the medium was significantly increased during the overall culture period (16 days), with maximum values 3.0-, 9.4- and 6.0-fold higher than those obtained in the batch cultures, respectively, even though the intracellular hGM-CSF content was not significantly varied by the perfusion rate. In terms of the total amount of hGM-CSF secreted, 205.5, 1073.2 and 1246.3 μg accumulated in the perfusate within 16 days at the perfusion rates of 0.5, 1.0 and 2.0 day−1, respectively. It was concluded that the beneficial effect of perfusion on the production of hGM-CSF originated from the reduced proteolytic degradation due to the lower protease activity caused by the perfusion. Additionally, the cell growth and physiology in the perfusion culture were somewhat negatively affected by the increased perfusion rate, although the dry cell density steadily increased, and as a result, 19.4, 22.4 and 22.9 g l−1 of maximum cells were obtained with perfusion rates of 0.5, 1.0 and 2.0 day−1, respectively. This work highlighted the importance of proteolytic degradation in plant cell cultures for the production of secretory proteins and the feasibility of perfusion strategies for the continuous production of foreign proteins by the prevention of protein loss due to proteolytic enzymes. 相似文献
20.
W. M. Van der Krieken A. F. Croes G. W. M. Barendse G. J. Wullems 《Physiologia plantarum》1988,74(1):113-118
Benzyladenine (BA) was found to regulate the number of flower buds regenerated in vitro from pedicel tissue of tobacco. Flower bud induction was particularly sensitive to BA levels in the range of 0.45 to 1.0 μ M , where a two-fold increase in concentration caused a threefold rise in the number of buds. When tissues were fed radioactive BA for 24h, only 9–12% of the counts were recovered in the original compound. The rest was present in metabolites, tentatively identified as the mono-, di- and triribotides, 7- and 9-glucosides and 9-riboside of BA. The amount of growth regulator taken up and the quantities of BA and its metabolites in the explants were all linearly related to the concentration of the medium. The internal BA concentration was ca 60% of the level in the medium after 24 h. When the concentration in the medium was raised, relatively more BA remained in the non-conjugated form. However, this change in the equilibrium between BA and the conjugates is too small to account for the steep rise in the curve representing concentration vs effect between 0.45 and 1.0 μ M . 相似文献