松茸与香菇原生质体融合的研究

以获得利于半人工或人工栽培优良松茸菌株为目的，利用松茸与香菇分离纯化的再生原生质体对潮霉素自然抗药性的差异，结合原生质体灭活为融合子筛选的依据。在PEG、Ca^2 系统中以30％PEG4000，30℃处理25min，诱导松茸与香菇良用菌原生质体融合，获融合子5株，融合率0．45％。     

松茸与香菇原生质体融合子生物学特性的研究

以获得利于半人工或人工栽培优良松茸菌株为目的，利用松茸与香菇分离纯化的再生原生质体[1]对潮霉素自然抗药性的差异，结合原生质体灭活为融合子筛选的依据，在PEG、Ca^2 系统中以30％PEG4000、30℃处理25分钟，诱导松茸与香菇两食用菌原生质体融合，获融合子5株(F1-5)[2]，对融合子进行了部分生物学特性的分析检测。     

平菇与香菇融合子的综合鉴定

原生质体融合研究,属于细胞工程重大理论研究课题。国内外学者都想利用生物工程的理论和技术,来探讨原生质体融合后基因重组遗传规律,在理论上和学术上均具有重大意义。在实践上也为克服远缘杂交不亲和性,为选育新品种提供一条可能的途径。 众所周知,平菇具有生长周期短,易栽培,产量高等特点,但其品质较差,香菇味道鲜美,营养丰富,经济价值高,但香菇生长周期长,产量低,抗逆性差,北方很少栽培。长期以来人们就设想把两者的优点结合起来,但因亲缘关系较远,靠常规杂交不可能实现。 本项研究以平菇和香菇为材料,进行两者原生质体融合遗传规律研究。首先分离并纯化平菇和香菇单孢系(单孢克隆成一个无性系),测定单孢系基因型,以锁状联合作为筛选融合子的细胞标记。用溶壁酶将平菇和香菇单孢系制备出原生质体,而后以PEG作为融合剂使两者异源原生质体融合,利用基因互补原理和细胞标记筛选出融合子,进一步将融合于材料培养出子实体。现将融合子综合分析和鉴定如下: 1.观察统计融合子形成的子实体,其菌伞的形态、颜色、生长习性具有双亲性状。 2.对融合子的氨基酸含量测定,其氨基酸含量有     

平菇灭活原生质体融合育种研究

干菇种间原生质体融合的成功,使得平菇的遗传育种工作出现了崭新的面貌。但是,在开展原生质体融合时,通常对亲本菌株加入一些遗传标记,以便融合后顺利地挑选融合子。在实践中人们又发现所加的遗传标记,往往会因为干扰了其正常的代谢途径,而降低了亲本菌株的生产能力,对育种的效果不利;同时,做遗传标记又会耗时、费工,消耗大量的人力、物力,增加育种工作的时间和成本。因此,自1977年以来,人们就开始了用灭活原生质体进行微生物融合育种的尝试。美味平菇A76和佛罗里达平菇A95是侧耳属两个不同的种,为了将它们的优良性状结合在一起,人工创造新品种,我们采用灭活原生质体融合技术,经过两年的研究,获得了美味平菇A76和佛罗里达平菇A95种间融合子。对融合子进行了多代选育,获得了性状稳定的高产优质新菌株。现将研究结果报道如下。     

细胞工程株平香1号培育简报

食用菌原生质体融合是近年来兴起的细胞工程新技术,它为克服远缘杂交的不亲合性人工培育新品种提供了可能。 香菇味美,营养丰富,但生育期长,抗性差,产量低,在北方很少栽培。平菇生育期短,抗杂菌力强,易栽培,产量高,但品质较差。平菇和香菇是不同属间的食用菌,为了将它们的优良特性结合在一起,人工创造新品种,我们于1985年立题用原生质体融合技术,经几年的研究,得到香菇、平菇融合子,并对融合子综合鉴定,获得充分证据,于1990年通过省级鉴定。而后对融合子多代选育,获得性状稳定的高产优质新菌株,命名平香1号。经3次产量中试,已大面积推广。现将菌株培育及产量中试简况报道如下:     

香菇DNA导入平菇原生质体及转化子鉴定研究

采用氯化苄方法提取香菇总ＤＮＡ，用Ｇｅｎｅ Ｐｕｌｓｅｒ Ⅱ电击系统将香菇ＤＮＡ导入平菇单核原生质体，通过香菇ＤＮＡ的导入，利用基因互补原理获得了能出菇的转化子１－１和１３－４８，并对转化子进行了拮抗试验、菌丝生长速度分析，酯酶同工酶分析和ＲＡＰＤ分析。     

外源抗药性基因导入香菇体内的研究

利用PEG转化法将携有潮霉素抗药性基因的质粒载体导入香菇原生质体内，获得了抗性转化子，但转化率较低，每微克DNA仅有0．5个转化子。点杂交证实，外源基因已整合到香菇染色体；不同转化子在抗笥平板上生长速率不同，且转化子有丝分裂是稳定的。香菇转基因技术的成功，为利用该技术克隆香菇内源基因及启动子，将外源有益目的基因导入香菇体内，为培育香菇基因工程菌株提供了可能。     

我国培育出远缘杂交新菌种

我国培育出远缘杂交新菌种河北农业大学教授刘振岳等人利用细胞融合技术．在世界上首次培育了香菇与平菇两个属间的远缘杂交新菌种──平香一号。专家认为，这是生物工程领域的重大突破。对平菇与香菇异属间原生质体融合的研究，一直是国际生物工程技术研究界的重大理论课...     

黑木耳菌丝原生质体再生研究简报

在细胞融合技术中,使原生质体高频率地再生是其中至关重要的一环。然而,在食用菌的细胞融合研究中,诸如已报道的香菇、平菇、草菇等,其原生质体的再生率均较低,一般在10～1%之间,有的甚至在1%以下,这就给进一步工作带来一定困难。造成原生质体再生率低下的原因,可能是由原生质体自身质量所引起的。已有报道证实,平菇原生质体有36%的细胞无核。我们认为,更主要的原因可能还在于对原生质体再生的条件研究不够。目前还未见有关再生条件的研究报告。我们在成功地制备黑木耳菌丝原生质体的基础上,对其再生的某些条件进行了初步的研究。     

信息与传递

我国获得食用菌属间杂种河北农业大学副教授刘振岳等,五年来致力于平菇和香菇属间原生质体融合的研究,获得食用菌属间杂种,为远缘杂交培育新菌种奠定了基础。专家认为,这是生物工程上的一项重大成就。属于侧耳属的平菇与香菇属的香菇异属间原生质体融合的研究,一直是国际生物工程技术研究的重大理论课题。其目的在于解决远缘杂交不亲和的问题,培育出具有平菇产量高、生长周期短、易栽培管理、抗逆性强的优势,又具有香菇独特香味、品质好的远缘新品种。刘振岳与中国科学院遗传所合作进行的     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [³-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10^-6-10^-4 mmol/L) stimulated [³-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [³-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10^-6-10^-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl₂ for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.