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1.
Transformation of cereals via Agrobacterium and the pollen pathway: a critical assessment 总被引:1,自引:0,他引:1
Peter Langridge Reinhold Brettschneider Paul Lazzeri † Horst Lörz 《The Plant journal : for cell and molecular biology》1992,2(4):631-638
It has been proposed that transgenic plants of cereals can be generated by inoculating florets with Agrobacterium at or near anthesis. This procedure is shown to lead to the production of embryos of wheat and barley with enhanced resistance to antibiotic selection. It has also been possible to recover plants of wheat, barley and maize that gave positive hybridization signals with probes produced from within the T-DNA of the Agrobacterium vector. However, no evidence was found for transmission of the bands detected by hybridization in the progeny of the putative transgenic plants nor could enzyme activity associated with the resistance genes be found in plant extracts. Furthermore, undigested genomic DNA from the plants that were positive when probed with the T-DNA, showed hybridization to bands smaller than the genomic DNA. It is suggested that the apparent transformation is an artifact of the procedure and does not reflect transformation of the plant nuclear genome. 相似文献
2.
Molecular characterisation of two novel maize LRR receptor-like kinases, which belong to the SERK gene family 总被引:7,自引:0,他引:7
Baudino S Hansen S Brettschneider R Hecht VF Dresselhaus T Lörz H Dumas C Rogowsky PM 《Planta》2001,213(1):1-10
Genes encoding two novel members of the leucine-rich repeat receptor-like kinase (LRR-RLK) superfamily have been isolated
from maize (Zea mays L.). These genes have been named ZmSERK1 and ZmSERK2 since features such as a putative leucine zipper (ZIP) and five leucine rich repeats in the extracellular domain, a proline-rich
region (SPP) just upstream of the transmembrane domain and a C-terminal extension (C) after the kinase domain identify them
as members of the SERK (omatic mbryogenesis eceptor-like inase) family. ZmSERK1 and ZmSERK2 are single-copy genes and show 79% identity among each other in their nucleotide sequences. They share a conserved intron/exon
structure with other members of the SERK family. In the maize genome, ZmSERK1 maps to position 76.9 on chromosome arm 10L and ZmSERK2 to position 143.5 on chromosome arm 5L, in regions generally not involved in duplications. ZmSERK1 is preferentially expressed in male and female reproductive tissues with strongest expression in microspores. In contrast,
ZmSERK2 expression is relatively uniform in all tissues investigated. Both genes are expressed in embryogenic and non-embryogenic
callus cultures.
Received: 20 June 2000 / Accepted: 25 September 2000 相似文献
3.
Maike Miriam Grube Elena von der Lippe Martin Schlaud Anna-Kristin Brettschneider 《PloS one》2015,10(3)
BackgroundCurrent studies suggest that the beneficial effect of breastfeeding on overweight and obesity may have been largely overestimated. We examined the relationship between >4 months of full breastfeeding and overweight/obesity in children living in Germany.MethodsWe analyzed retrospectively collected data on breastfeeding from children aged 3–17 years who participated in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS baseline study) between 2003 and 2006 (n = 13163). To minimize confounding, we applied propensity score matching and multivariate logistic regression analyses to estimate the effect of breastfeeding on childhood overweight and obesity.ResultsAdjusted analyses of the matched dataset (n = 8034) indicated that children who were breastfed for <4 months had a significant reduction in the odds of overweight (OR 0.81 [95% CI 0.71–0.92]) and obesity (OR 0.75 [95% CI 0.61–0.92]) compared to children who were not breastfed or who were breastfed for a shorter duration. Further analyses stratified by age group showed that the association was strongest in children aged 7–10 years (OR 0.67 [95% CI 0.53–0.84] for overweight and OR 0.56 [95% CI 0.39–0.81] for obesity), while no significant effect could be seen in other age groups.DiscussionOur findings support the hypothesis that breastfeeding does have a beneficial effect on childhood overweight and obesity, although the effect seems to be strongest in children of primary school age. 相似文献
4.
Martin Gorges Hans-Peter Müller Dorothée Lulé Kelly Del Tredici Johannes Brettschneider Jürgen Keller Katharina Pfandl Albert C. Ludolph Jan Kassubek Elmar H. Pinkhardt 《PloS one》2015,10(11)
Background
The neuropathological process underlying amyotrophic lateral sclerosis (ALS) can be traced as a four-stage progression scheme of sequential corticofugal axonal spread. The examination of eye movement control gains deep insights into brain network pathology and provides the opportunity to detect both disturbance of the brainstem oculomotor circuitry as well as executive deficits of oculomotor function associated with higher brain networks.Objective
To study systematically oculomotor characteristics in ALS and its underlying network pathology in order to determine whether eye movement deterioration can be categorized within a staging system of oculomotor decline that corresponds to the neuropathological model.Methods
Sixty-eight ALS patients and 31 controls underwent video-oculographic, clinical and neuropsychological assessments.Results
Oculomotor examinations revealed increased anti- and delayed saccades’ errors, gaze-palsy and a cerebellary type of smooth pursuit disturbance. The oculomotor disturbances occurred in a sequential manner: Stage 1, only executive control of eye movements was affected. Stage 2 indicates disturbed executive control plus ‘genuine’ oculomotor dysfunctions such as gaze-paly. We found high correlations (p<0.001) between the oculomotor stages and both, the clinical presentation as assessed by the ALS Functional Rating Scale (ALSFRS) score, and cognitive scores from the Edinburgh Cognitive and Behavioral ALS Screen (ECAS).Conclusions
Dysfunction of eye movement control in ALS can be characterized by a two-staged sequential pattern comprising executive deficits in Stage 1 and additional impaired infratentorial oculomotor control pathways in Stage 2. This pattern parallels the neuropathological staging of ALS and may serve as a technical marker of the neuropathological spreading. 相似文献5.
Widl K Brettschneider J Schattauer D Süssmuth S Huber R Ludolph AC Tumani H 《Neurochemical research》2007,32(7):1163-1168
We aimed to establish age-related reference values for Erythropoietin (EPO) in cerebrospinal fluid (CSF) and to evaluate concentrations
in neurological diseases. CSF and serum EPO was measured in controls with tension-type headache (CTTH), in patients with ALS,
dementia and depression using ELISA technique.
Stability experiments showed CSF EPO to be stable for two and a half months and over two thaw/freeze cycles. A positive correlation
of CSF EPO with age was found (P < 0.01). We found a CSF/serum EPO concentration ratio of 0.126, pointing towards an intrathecal synthesis of EPO. The ALS
group showed significantly lowered CSF EPO compared to age-matched CTTH (P < 0.012), whereas the dementia and depression group showed no significant differences compared to CTTH.
The establishment of age-related reference values in a large cohort of controls will improve the interpretation of future
CSF EPO evaluations in neurological diseases.
The authors have not reported any conflicts of interest. 相似文献
6.
7.
Görgens A Beckmann J Ludwig AK Möllmann M Dürig J Horn PA Rajendran L Giebel B 《The international journal of biochemistry & cell biology》2012,44(7):1121-1132
Freshly isolated human hematopoietic stem and progenitor cells (HSPCs) are small and round cells which upon cultivation adopt a polarized morphology and redistribute certain cell surface antigens. To functionally dissect this polarization process, we addressed impacts of protein synthesis, HSPC trafficking, cytoskeleton organization or lipid raft integrity on the establishment and maintenance of the cell polarity of human HSPCs. Effects on the morphology, sub-cellular distribution of lipid raft-associated molecular polarization markers (Flotillin-1, Flotillin-2, ICAM-3) and in vitro migration capabilities of treated cells were studied. We could distinguish two levels of cellular polarization, a molecular and a morphological level. Our data suggest that protein synthesis, lipid raft integrity and enzymatic activities of PI3K and aPKC are required to organize the molecular cell polarity. The morphological cell polarization process, however, also depends on actin polymerization and rho-GTPase activities. In summary, our data qualify HSPC polarization processes as new pharmaceutical target to interfere with migratory and with homing capabilities of HSPCs. 相似文献
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9.
Reproducibility testing of RAPD,AFLP and SSR markers in plants by a network of European laboratories 总被引:21,自引:0,他引:21
Jones C.J. Edwards K.J. Castaglione S. Winfield M.O. Sala F. van de Wiel C. Bredemeijer G. Vosman B. Matthes M. Daly A. Brettschneider R. Bettini P. Buiatti M. Maestri E. Malcevschi A. Marmiroli N. Aert R. Volckaert G. Rueda J. Linacero R. Vazquez A. Karp A. 《Molecular breeding : new strategies in plant improvement》1997,3(5):381-390
A number of PCR-based techniques can be used to detect polymorphisms in plants. For their wide-scale usage in germplasm characterisation and breeding it is important that these marker technologies can be exchanged between laboratories, which in turn requires that they can be standardised to yield reproducible results, so that direct collation and comparison of the data are possible. This article describes a network experiment involving several European laboratories, in which the reproducibility of three popular molecular marker techniques was examined: random-amplified fragment length polymorphism (RAPD), amplified fragment length polymorphism (AFLP) and sequence-tagged microsatellites (SSR). For each technique, an optimal system was chosen, which had been standardised and routinely used by one laboratory. This system (genetic screening package) was distributed to different participating laboratories in the network and the results obtained compared with those of the original sender. Different experiences were gained in this exchange experiment with the different techniques. RAPDs proved difficult to reproduce. For AFLPs, a single-band difference was observed in one track, whilst SSR alleles were amplified by all laboratories, but small differences in their sizing were obtained. 相似文献
10.
Johannes Brettschneider Anne Czerwoniak Makbule Senel Lubin Fang Jan Kassubek Elmar Pinkhardt Florian Lauda Tamara Kapfer Sarah Jesse Vera Lehmensiek Albert C. Ludolph Markus Otto Hayrettin Tumani 《PloS one》2010,5(8)