Gibberellin-mediated RGA-LIKE1 degradation regulates embryo sac development in Arabidopsis

[EN] Ovule development is essential for plant survival, as it allows correct embryo and seed development upon fertilization. The female gametophyte is formed in the central area of the nucellus during ovule development, in a complex developmental programme that involves key regulatory genes and the plant hormones auxins and brassinosteroids. Here we provide novel evidence of the role of gibberellins (GAs) in the control of megagametogenesis and embryo sac development, via the GA-dependent degradation of RGA-LIKE1 (RGL1) in the ovule primordia. YPet-rgl1.17 plants, which express a dominant version of RGL1, showed reduced fertility, mainly due to altered embryo sac formation that varied from partial to total ablation. YPet-rgl1.17 ovules followed normal development of the megaspore mother cell, meiosis, and formation of the functional megaspore, but YPet-rgl1.17 plants had impaired mitotic divisions of the functional megaspore. This phenotype is RGL1-specific, as it is not observed in any other dominant mutants of the DELLA proteins. Expression analysis of YPet-rgl1.17 coupled to in situ localization of bioactive GAs in ovule primordia led us to propose a mechanism of GA-mediated RGL1 degradation that allows proper embryo sac development. Taken together, our data unravel a novel specific role of GAs in the control of female gametophyte development.We wish to thank the IBMCP microscopy facility, and Ms J. Yun for technical assistance. We also thank Jennifer Nemhauser (University of Washington, USA) for the HACR sensor. Cambridge proofreading (https://proofreading.org/order/) provided proofreading and editing of this manuscript. This work was supported by grants from the Spanish Ministry for Science and Innovation-FEDER [BIO2017-83138R] to MAP-A and National Science Foundation [MCB-0923727] to JMA. 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Clinical and genetic profiles of patients with X-linked agammaglobulinemia from southeast Turkey: Novel mutations in BTK gene

PubMedID: 30072168Background: X-linked agammaglobulinemia (XLA) is characterized by absent or severely reduced B cells, low or undetectable immunoglobulin levels, and clinically by extracellular bacterial infections which mainly compromise the respiratory tract. We aimed to analyze the clinical, immunological and genetic characteristics of 22 male children with XLA. Methods: Twenty-two children with XLA from 12 unrelated families were enrolled in this study. Clinical and demographic features of patients, serum immunoglobulin levels, percentage of B cells and BTK gene mutations were reviewed retrospectively. Results: We identified 12 different mutations in 22 patients from 12 unrelated families. The most frequent type of mutation was premature stop codon (33.3%). Ten mutations had been reported previously including three missense mutations (c.1774T>C, c.1684C>T, c.83G>T), three premature stop codons (c.1558C>T, c.1573C>T, c.753G>A), two splice-site (c.683-1G>A, c.1567-12_1567-9delTTTG) and two small nucleotide deletions (c.902-904_delAAG, c.179_181delAGA). Two novel mutations of the BTK gene were also presented and included one splice-site mutation (c.391+1G>C) and one premature stop codon mutation (c.1243_1243delG). Six out of 12 mutations of the BTK gene were located in the SH1 domain, two in the PH domain, two in the SH3 domain and two in the SH2 domain. Three patients had a history of severe infection before diagnosis. We did not identify any correlation between severity of clinical symptoms and the genotype. Conclusions: Our results show that mutations in southeast Turkey could be different from those in the rest of the world and molecular genetic tests are an important tool for early confirmed diagnosis of XLA. © 2018 SEICA

The clinical and immunologic features of patients with Immunoglobulin A deficiency: A tertiary center experience from Turkey

Congress of the European-Academy-of-Allergy-and-Clinical-Immunology (EAACI) -- MAY 26-30, 2018 -- Munich, GERMANYWOS: 000441690402245…European Acad Allergy & Clin Immuno

Parenteral knowledge of anaphylaxis and their performance in epinephrine auto-injector use: A survey in Turkish patients

Congress of the European-Academy-of-Allergy-and-Clinical-Immunology (EAACI) -- JUN 01-05, 2019 -- Lisbon, PORTUGALWOS: 000480254005110…European Acad Allergy & Clin Immuno

Clinical and genetic profiles of patients with X-linked agammaglobulinemia from southeast Turkey

Congress of the European-Academy-of-Allergy-and-Clinical-Immunology (EAACI) -- MAY 26-30, 2018 -- Munich, GERMANYWOS: 000441690405196…European Acad Allergy & Clin Immuno

Ataxia-Telangiectasia Clinical and Laboratory Features: Single Center Results

Ataxia-telangiectasia (A-T) is characterized by progressive cerebellar ataxia, oculocutaneous telangiectasia, chronic sinopulmonary disease, a high incidence of malignancy, and immunological deficiencies. The mutated gene, ataxia-telangiectasia mutation (ATM), has been mapped to chromosome 11 (11q22-23). The incidence of A-T is about 1-3 per 40,000-100,000 births. The aim of this study was to evaluate the clinical and immunological features of the patients with A-T. Medical records of 49 patients with A-T were reviewed retrospectively. Demographic features, laboratory findings, genetic analysis, and the clinical data recorded during the follow-up period were reviewed. Medical records of 49 patients (26 female) were included in the study. Mean age at the time of study was 9 years 3 months. Mean follow-up period was 4.5 years. Mean diagnostic delay was 18 months. Consanguinity was found in 85.7% of the patients. Malignancy was present in 8.2% of first-degree and in 34.7% of second-degree relatives. Lymphocytopenia was found in 29 (59.2%) patients. Mean serum alpha-fetoprotein level was 171.6 ± 138.6 ng/dL. Intravenous immunoglobulin replacement therapy was required in 28 (57.1%) patients. Sinopulmonary infections were the most common infections (51%). Fifteen (30.6%) patients became wheelchair dependent. Malignancy occurred in 6 (12.3%) patients. One patient with acute lymphoblastic leukemia had successful bone narrow transplantation. The other 5 patients died during the follow-up period. Mutation in ATM was found in 34 (69.4%) patients. Of these, 7 patients were found to have novel mutations. A-T is difficult to treat and has a poor prognosis because of its multisystem involvement. Management strategies focus on the surveillance, prevention, and treatment of the major causes of morbidity related to A-T. © Copyright 2018, Mary Ann Liebert, Inc. 2018.61/50Medical records of patients with A-T were retrospectively reviewed. A-T was diagnosed according to criteria proposed by the European Society for Immunodeficiencies (www.esid .org). Patients with missing medical records were accessed through phone. Patients were excluded if they could not be reached through phone or if their medical records were unavailable. This study was approved by Cukurova University Institutional Review Board and Ethics Committee (Project No: 61/50). Written informed consent was obtained from the parents of each patient who was enrolled

Assessment of prevalence of allergic sensitivity in pediatric age group by the use of skin test

Meeting of the European-Academy-of-Allergy-and-Clinical-Immunology -- JUN 11-15, 2016 -- Vienna, AUSTRIAWOS: 000383679803107…European Acad Allergy & Clin Immuno