Biochemical and cytological studies of genetic transfer from the Mv genome of Aegilops ventricosa into hexaploid wheat

A double interspecific oross {Triticum turgidum (AB) var. rubroatrum H-l-1 x Ae. ventvicosa (DM°) AP-l} x T.aestivum (ABD) cv. Almatense H-10-1S was carried out in 1950 by M. Alonso Peña (Cuenca, Spain) and 70 Unes were devived from it by vepeated selfing (Unes H-93-1 thvough 70). Pveliminavy biochemical evidence indicated genetic tvansfev fvom the M° genome of Ae.ventvicosa into some of these Unes. A more detailed biochemical and cytological characteriza tion of the H-93- Unes was undertaken. A progress report of these studies is presented here. Fourten biochemical systems, each representing a set of up to 4 homoeologous loci, weve investigated in the vavental material, in the H-93- Unes, and in Ae. squavrosa (DD), Ae. comosa (MM) and Ae. uniaristata (M^-M11). Biochemical markers controlled by the A or B genomes of one or both wheat parents weve distributed in the H-93- Unes as expected if the egcells fvom the self-stevile ABDM0 hybvid, rescued by the ABD polen, cavvied the complete A and B genomes from T. tuvgidum. The distvibution of biochemical mavkevs contvolled by the D genomes of one ov both D genome parents indicated that most of the eggcells from the ABDM0 hybrid carvied most of the D genome, i.e. 3 out of 8 markers of the former tupe were absent in a few Unes each, ind.icating incomplete homology between the two D genomes, non-homologous transfer or deletion. Biochemical characters present in Ae. ventricosa (DM°), Ae. comosa (M), Ae. uniaristata (M11) and absent in T. aestivum (ABD), Ae. squarrosa (D) and T. tuvgidum (AB) were selected as M° genome markers. Two of these markers were not transmited to the H-93- Unes, three were tvansmitted with low fvequency and one with a high fvequency. Resistance to Erisiphe graminis was determined by Dosba and Doussinault at Rennes and was found to be transmitted with low fvequency. Somatic chromosome numbers of the H-93- Unes were counted and all weve found to be hexaploid. Meiosis was studied in Unes cavvying M° genome mavkevs and in their hybrids with the T. aestivum parent, to determine the máximum numbev of alien chvornosornespvesent in each Une. The joint considevation of the biochemical and the cytological evidence se^me to indícate that the genetic tvansfev has taken place by chvomosome substitution and by vecombination

Resistance to eyespot (Pseudocercosporella herpotricoides) and distribution of biochemical markers in hexaploid lines derived from double cross (Triticum turgidum x Aegilops ventricosa) x T. aestivum

There are not good intraspecific sources of resistance to the eyespot disea se of wheat, aaused by Cercosporella herpotrichoides Fvon . The -ínterspecifia transfer of genes for resistanoe from Aegitops ventricosa into hexaploid wheat has been only partially achieved, because the degree of resistanoe attained is not as high as that of the donor. We report here on the transfer of resistanoe in a double oross (Triticum turgidum var. rubroatrwv H-1-1 x Ae.ventricosa AP-D x T.aestivum cv. Almatense H-10-15. The high level of resistanoe in a high proportion of the lines strongly suggests a simple genetic control for this oharacter (possibly by one major gene). The gene(s) responsible for resistanoe in the selected lines must be associa ted with the D genome of Aegilops ventricosa on the basis of a detailed study of the distribution of biochemioal markers in the H-93 lines. These results do not exelude that genes with similar effeets might be looated in the M° genome

Differential in vitro and in vivo effect of barley cysteine and serine protease inhibitors on phytopathogenic microorganisms

Protease inhibitors from plants have been involved in defence mechanisms against pests and pathogens. Phytocystatins and trypsin/α-amylase inhibitors are two of the best characterized protease inhibitor families in plants. In barley, thirteen cystatins (HvCPI-1 to 13) and the BTI-CMe trypsin inhibitor have been previously studied. Their capacity to inhibit pest digestive proteases, and the negative in vivo effect caused by plants expressing these inhibitors on pests support the defence function of these proteins. Barley cystatins are also able to inhibit in vitro fungal growth. However, the antifungal effect of these inhibitors in vivo had not been previously tested. Moreover, their in vitro and in vivo effect on plant pathogenous bacteria is still unknown. In order to obtain new insights on this feature, in vitro assays were made against different bacterial and fungal pathogens of plants using the trypsin inhibitor BTI-CMe and the thirteen barley cystatins. Most barley cystatins and the BTI-CMe inhibitor were able to inhibit mycelial growth but no bacterial growth. Transgenic Arabidopsis plants independently expressing the BTI-CMe inhibitor and the cystatin HvCPI-6 were tested against the same bacterial and fungal pathogens. Neither the HvCPI-6 expressing transgenic plants nor the BTI-CMe ones were more resistant to plant pathogen fungi and bacteria than control Arabidopsis plants. The differences observed between the in vitro and in planta assays against phytopathogenic fungi are discusse

Análisis epidemiológico de geohelmintos de importancia clínica en Perú 2015-2018

Analiza las características epidemiológicas de los geohelmintos de importancia clínica en Perú desde los años 2015 al 2018. Se realizó un estudio cuantitativo, descriptivo, observacional, retrospectivo y transversal. Se estudió una base de datos brindada por el Ministerio de Salud con 9583 atenciones reportadas en Perú por geohelmintiasis dentro del periodo 2015 – 2018. Se utilizó el programa SPSS versión 25 para obtener la frecuencia y así elaborar las tablas y gráficos. Se halló un total de 9583 atenciones por geohelmintiasis en el periodo 2015- 2018, con mayor frecuencia en Amazonas 9496 (99.11%). Siendo el género femenino el predominante 58% (5539) respecto del masculino 42% (4044), mientras que el grupo etario más común fueron las niñas de 1 a 4 años (1872 atenciones). El agente causal más frecuente fue Ascaris lunbricoides, siendo la Ascariasis no especificada (B77.9) la que obtuvo el mayor número de atenciones 8945 (93.3%). Dentro de los establecimientos de salud, el mayor número de atenciones fue del nivel 1 (89.3%), y su categoría I – 3 la más frecuente (56%) dentro de ese nivel. En conclusión, en el Perú, existe una alta frecuencia de geohelmintos, especialmente en regiones endémicas como Amazonas donde predomina Ascaris lumbricoides, que afecta drásticamente a niños en edad temprana. Por consiguiente, resulta relevante tomar medidas para que esta frecuencia de parasitosis disminuya como promoción de la salud y medidas que promuevan de conciencia sanitarias

Component-Resolved in Vitro Diagnosis in Peach-Allergic Patients

BACKGROUND: The in vitro diagnosis of pollen-related food allergy presents low specifi city and reproducibility with many conventional extracts. This can be improved using natural purifi ed allergens, recombinant purifi ed allergens, or both. OBJECTIVE: We compared specifi c immunoglobulin (Ig) E determination (sIgE), the basophil activation test (BAT), the histamine release test (HRT), and the cellular allergen stimulation test (CAST) using natural and recombinant allergens in the diagnosis of peach allergy. METHODS: Thirty-two peach allergic patients were studied. Skin prick tests were performed with commercial peach and extract with Mal d 1, nPru p 3, and profi lin (nPho d 2). sIgE, BAT, CAST, and HRT were determined using rPru p 3, rMal d 3, rBet v 1, rMal d 1, and rMal d 4. RESULTS: Agreement between the techniques was good with all the allergens, except HRT with rMal d 1 and rMal d 4. With rPru p 3, sIgE, CAST, BAT, and HRT showed sensitivity values of 88%, 81%, 72%, and 69% and specifi city values of 100%, 93%, 97%, and 83%, respectively. In patients with systemic symptoms or contact urticaria, the values were 100%, 85%, 81%, and 81%. In patients with oral allergy syndrome, sensitivity to profi lins or homologues of Bet v 1 was detected in 100% of the cases by all the techniques, except by HRT with rMal d 1, which detected 66% of the cases. CONCLUSIONS: The use of single allergens in the in vitro diagnosis of peach allergy by specifi c IgE determination, BAT, and CAST offers high specifi city and sensitivity, with better results than the HRT

Sensitization profiles to purified plant food allergens among pediatric patients with allergy to banana.

Banana fruit allergy is well known, but neither immunoglobulin E recognition patterns to purified plant food allergens nor true prevalences of putative banana allergens have been established. This study aimed to characterize β-1,3-glucanase and thaumatin-like protein (TLP) as banana allergens, testing them, together with other plant food allergens, in 51 children with allergic reactions after banana ingestion and both positive specific IgE and skin prick test (SPT) to banana. Banana β-1,3-glucanase and TLP were isolated and characterized. Both banana allergens, together with kiwifruit TLP Act d 2, avocado class I chitinase Pers a 1, palm pollen profilin Pho d 2 and peach fruit lipid transfer protein (LTP) Pru p 3, were tested by in vitro and in vivo assays. Banana β-1,3-glucanase (Mus a 5) was glycosylated, whereas banana TLP (Mus a 4) was not, in contrast with its homologous kiwi allergen Act d 2. Specific IgE to both banana allergens, as well as to peach Pru p 3, was found in over 70% of sera from banana-allergic children, and Mus a 4 and Pru p 3 provoked positive SPT responses in 6 of the 12 tested patients, whereas Mus a 5 in only one of them. Both peptidic epitopes and cross-reactive carbohydrate determinants were involved in the IgE-binding to Mus a 5, whereas cross-reactivity between Mus a 4 and Act d 2 was only based on common IgE protein epitopes. Profilin Pho d 2 elicited a relevant proportion of positive responses on in vitro (41%) and in vivo (58%) tests. Therefore, Mus a 4 and LTP behave as major banana allergens in the study population, and profilin seems to be also a relevant allergen. Mus a 5 is an equivocal allergenic protein, showing high IgE-binding to its attached complex glycan, and low in vivo potency

Transfer of resistance to eyespot disease from Aegilops ventricosa to wheat

The extraspecific transfer of genes into cultivated plants is of considerable interest both in basic and applied terms (Sears, 1956; Riley and Kimber 1966). The wild grass Aegilops ventricosa has been recognised for almost 30 years as an important potential donor of genes that determine characters of agronomic interest. More specifically, Sprague (1936) discovered in this species a high level of resistance to the fungus Pseudocercosporella herpotrichoides, which causes eyespot disease. This disease is responsible for considerable lodging and reductions of yield in extensive áreas of wheat cultivation. The level of resistance of wheat cultivars is too low, even among the less susceptible ones (Capelle Desprez and Cerco) and no single genes for resistance had been described in any species. Attemps to transfer resistance from Ae.ventricosa to wheat had been only partially successful. The purpose of this paper is to review work carried out in our laboratory for the past 12 years on the transfer of genes between these two species. This work has led to the recent demonstre^ tion of a major dominant gene for resistance, which confers a high level of resistance to cultivated wheat

Introducción de genes extraespecíficos en el trigo

La introducción de caracteres extragenéricos o extraespecíficos en plan tas cultivadas tiene interés teórico y una reconocida importancia práctica (ver p.ej. ref.1). En el caso de los trigos cultivados, pueden actuar como donadores de genes que controlan caracteres de calidad, de resistencia a agentes patógenos, etc., especies afines de los géneros Sécale, Agropyron y Aegilops. Los métodos empleados para la introducción de estos caracteres son variados y dependen de la afinidad existente entre la especie donadora y la receptora. El proceso de transferencia requiere, en primer lugar, salvar los impe_ dimentos que se presentan para el acceso del material genético extraño al núcleo receptor y, posteriormente, lograr la integración estable de dicho material

Mimotope mapping as a complementary strategy to define allergen IgE-epitopes: peach Pru p 3 allergen as a model.

Lipid transfer proteins (LTPs) are the major allergens of Rosaceae fruits in the Mediterranean area. Pru p 3, the LTP and major allergen of peach, is a suitable model for studying food allergy and amino acid sequences related with its IgE-binding capacity. In this work, we sought to map IgE mimotopes on the structure of Pru p 3, using the combination of a random peptide phage display library and a three-dimensional modelling approach. Pru p 3-specific IgE was purified from 2 different pools of sera from peach allergic patients grouped by symptoms (OAS-pool or SYS-pool), and used for screening of a random dodecapeptide phage display library. Positive clones were further confirmed by ELISA assays testing individual sera from each pool. Three-dimensional modelling allowed location of mimotopes based on analysis of electrostatic properties and solvent exposure of the Pru p 3 surface. Twenty-one phage clones were selected using Pru p 3-specific IgE, 9 of which were chosen using OAS-specific IgE while the other 12 were selected with systemic-specific IgE. Peptide alignments revealed consensus sequences for each pool: L37 R39 T40 P42 D43 R44 A46 P70 S76 P78 Y79 for OAS-IgE, and N35 N36 L37 R39 T40 D43 A46 S76 I77 P78 for systemic-IgE. These 2 consensus sequences were mapped on the same surface of Pru p 3, corresponding to the helix 2-loop-helix 3 region and part of the non-structured C-terminal coil. Thus, 2 relevant conformational IgE-binding regions of Pru p 3 were identified using a random peptide phage display library. Mimotopes can be used to study the interaction between allergens and IgE, and to accelerate the process to design new vaccines and new immunotherapy strategie