Molekulare Charakterisierung einer Wildgerstenintrogression mit dem Gelbverzwergungsresistenzgen Ryd4Hb im Genom der Kulturgerste

Zusammenfassung Aus einer interspezifischen Kreuzung der Wintergerste Hordeum vulgare cv. 'Igri' mit der virusresistenten Wildgerste H. bulbosum wurden spaltende Kartierungspopulationen entwickelt, die eine 3HL-Introgression tragen, welche Resistenz gegenüber BYDV vermittelt. Die genetische Analyse einer BC2F4-Familie zeigte eine monohybride Aufspaltung der Resistenz mit dominanter Merkmalsausprägung. Es konnten bisher vier Gersten- Ankermarker und vier TC-Marker um das Resistenzgen Ryd4Hb kartiert werden. Zwei der aus den orthologen Bereichen des Reisgenoms abgeleiteten TC-Marker kosegregieren mit dem Resistenzgen Ryd4Hb. Stichwörter: Hordeum vulgare, Hordeum bulbosum, BYDV, Resistenz, Selektionsmarker   Abstract Interspecific crosses between winter barley H. vulgare cv. 'Igri' and a virus-resistant accession of the wild species H. bulbosum yielded mapping populations segregating with individuals resistant towards barley yellow dwarf virus. Genetic analysis of a BC2F4 family revealed a dominant inheritance of the resistance. GISH analysis indicated an Hb introgression on chromosome 3HL. Four 3HL barley anchor markers and four TC markers of the orthologous rice genome region, respectively, were mapped on either side of the resistance locus Ryd4Hb. Two of the TC markers cosegregated with the BYDV resistance. Keywords: Hordeum vulgare, Hordeum bulbosum, BYDV, resistance, selection marker

High-resolution mapping of Rym14Hb, a wild relative resistance gene to barley yellow mosaic disease

Barley yellow mosaic disease is caused by Barley yellow mosaic virus and Barley mild mosaic virus and leads to severe yield losses in barley (Hordeum vulgare) in Central Europe and East-Asia. Several resistance loci are used in barley breeding. However, cases of resistance-breaking viral strains are known, raising concerns about the durability of those genes. Rym14(Hb) is a dominant major resistance gene on chromosome 6HS, originating from barley's secondary genepool wild relative Hordeum bulbosum. As such, the resistance mechanism may represent a case of non-host resistance, which could enhance its durability. A susceptible barley variety and a resistant H. bulbosum introgression line were crossed to produce a large F2 mapping population (n = 7500), to compensate for a ten-fold reduction in recombination rate compared to intraspecific barley crosses. After high-throughput genotyping, the Rym14(Hb) locus was assigned to a 2Mbp telomeric interval on chromosome 6HS. The co-segregating markers developed in this study can be used for marker-assisted introgression of this locus into barley elite germplasm with a minimum of linkage drag

Influence of agglomeration and specific lung lining lipid/protein interaction on short-term inhalation toxicity

<p>Lung lining fluid is the first biological barrier nanoparticles (NPs) encounter during inhalation. As previous inhalation studies revealed considerable differences between surface functionalized NPs with respect to deposition and toxicity, our aim was to investigate the influence of lipid and/or protein binding on these processes. Thus, we analyzed a set of surface functionalized NPs including different SiO₂ and ZrO₂ in pure phospholipids, CuroSurf^TM and purified native porcine pulmonary surfactant (nS). Lipid binding was surprisingly low for pure phospholipids and only few NPs attracted a minimal lipid corona. Additional presence of hydrophobic surfactant protein (SP) B in CuroSurf^TM promoted lipid binding to NPs functionalized with Amino or PEG residues. The presence of the hydrophilic SP A in nS facilitated lipid binding to all NPs. In line with this the degree of lipid and protein affinities for different surface functionalized SiO₂ NPs in nS followed the same order (SiO₂ Phosphate ∼ unmodified SiO₂ < SiO₂ PEG < SiO₂ Amino NPs). Agglomeration and biomolecule interaction of NPs in nS was mainly influenced by surface charge and hydrophobicity. Toxicological differences as observed in short-term inhalation studies (STIS) were mainly influenced by the core composition and/or surface reactivity of NPs. However, agglomeration in lipid media and lipid/protein affinity appeared to play a modulatory role on short-term inhalation toxicity. For instance, lipophilic NPs like ZrO₂, which are interacting with nS to a higher extent, exhibited a far higher lung burden than their hydrophilic counterparts, which deserves further attention to predict or model effects of respirable NPs.</p

Two Decades of Brain Tumour Imaging with O-(2-[18F]fluoroethyl)-L-tyrosine PET: The Forschungszentrum Jülich Experience

PET using radiolabelled amino acids has become an essential tool for diagnosing brain tumours in addition to MRI. O-(2-[18F]fluoroethyl)-L-tyrosine (FET) is one of the most successful tracers in the field. We analysed our database of 6534 FET PET examinations regarding the diagnostic needs and preferences of the referring physicians for FET PET in the clinical decision-making process. The demand for FET PET increased considerably in the last decade, especially for differentiating tumour progress from treatment-related changes in gliomas. Accordingly, referring physicians rated the diagnostics of recurrent glioma and recurrent brain metastases as the most relevant indication for FET PET. The analysis and survey results confirm the high relevance of FET PET in the clinical diagnosis of brain tumours and support the need for approval for routine use