The Influence of Human-induced Erosion on the Soil Organic Carbon Stock in Vineyards of Fordon Valley

The aim of this paper has been to define the influence of accelerated erosion on basic properties and the SOM stocks of soils within vineyards located on western slopes of the Lower Vistula Valley. The study was conducted within four vineyards situated 30 km north-east from Bydgoszcz. During the field work 44 auger holes were made. On the basis of results of drilling, eight places for soil pits were selected. The study sites were characterised by considerable diversity of soil cover. The SOM stocks in studied profiles ranged from 2,98 to 63,9 kg m-2. The upper parts of the Lower Vistula Valley slopes were dominated by Luvisols developed from glacial tills. Pedons located in toe and foot slope positions represented Chernozems and Phaeozems developed from layered fluvial sediments. The translocation of soil was caused by accelerated erosion that heightened differentiation in the primeval SOM stocks. Although, the Luvisols were truncated in result of accelerated erosion, they were not significantly depleted in organic matter stocks. Most Chernozems and Phaeozems located in toe and foot slope positions were enhanced in SOM stocks due to accumulation of humus colluvial material on their surface. The short period of existence of vineyards makes it impossible to determine the impact of grass roots decay on carbon content in surface soil horizons between rows of vine

LAMTOR2 (p14) Controls B Cell Differentiation by Orchestrating Endosomal BCR Trafficking

B-cell development and function depend on stage-specific signaling through the B-cell antigen receptor (BCR). Signaling and intracellular trafficking of the BCR are connected, but the molecular mechanisms of this link are incompletely understood. Here, we investigated the role of the endosomal adaptor protein and member of the LAMTOR/Ragulator complex LAMTOR2 (p14) in B-cell development. Efficient conditional deletion of LAMTOR2 at the pre-B1 stage using mb1-Cre mice resulted in complete developmental arrest. Deletion of LAMTOR2 using Cd19-Cre mice permitted analysis of residual B cells at later developmental stages, revealing that LAMTOR2 was critical for the generation and activation of mature B lymphocytes. Loss of LAMTOR2 resulted in aberrant BCR signaling due to delayed receptor internalization and endosomal trafficking. In conclusion, we identify LAMTOR2 as critical regulator of BCR trafficking and signaling that is essential for early B-cell development in mice

mir-181A/B-1 controls thymic selection of treg cells and tunes their suppressive capacity

The interdependence of selective cues during development of regulatory T cells (Treg cells) in the thymus and their suppressive function remains incompletely understood. Here, we analyzed this interdependence by taking advantage of highly dynamic changes in expression of microRNA 181 family members miR-181a-1 and miR-181b-1 (miR-181a/b-1) during late T-cell development with very high levels of expression during thymocyte selection, followed by massive down-regulation in the periphery. Loss of miR-181a/b-1 resulted in inefficient de novo generation of Treg cells in the thymus but simultaneously permitted homeostatic expansion in the periphery in the absence of competition. Modulation of T-cell receptor (TCR) signal strength in vivo indicated that miR-181a/b-1 controlled Treg-cell formation via establishing adequate signaling thresholds. Unexpectedly, miR-181a/b-1–deficient Treg cells displayed elevated suppressive capacity in vivo, in line with elevated levels of cytotoxic T-lymphocyte–associated 4 (CTLA-4) protein, but not mRNA, in thymic and peripheral Treg cells. Therefore, we propose that intrathymic miR-181a/b-1 controls development of Treg cells and imposes a developmental legacy on their peripheral function

Towards understanding lymphocyte biology – lessons from murine models and primary immunodeficiencies

B and T lymphocytes constitute two essential components of the adaptive immune system. Both lineages arise from haematopoietic progenitors which reside in the bone marrow. Although final commitment and differentiation steps happen in different lymphoid organs, B and T cells share remarkable similarities. Both utilise Rag genes for somatically rearrange genes that encode their antigen recognition receptors. While B and T cells recombine different sets of genes, the Rag1/Rag2 genes complex recognises the same short motif in DNA to catalyse the reaction. Also, final commitment processes and selection of newly emerged receptors are similar and unique to them. Deriving a picture of the regulatory network of lymphocytes might also be seen as a model allowing to understand the basic mechanisms of non-coding RNA action. Moreover, it permits to deepen our understanding of fundamental processes in which B and T lymphocytes act. The first study summarised here describes the impact of microRNA-191 on the transcriptional regulatory network and posttranscriptional gene regulation. The transcription factors FoxP1, E2A and Egr1, were identified as direct downstream targets of miR-191. Deletion, as well as ectopic expression of miR-191, resulted in a developmental arrest in B lineage cells, indicating that fine-tuning of the combined expression levels of Foxp1, E2A, and Egr1, which in turn control somatic recombination and cytokine-driven expansion, constitutes a prerequisite for efficient B-cell development. Two other studies explored the molecular mechanism behind primary immunodeficiencies. The pivotal role of the LAMTOR2 (p14) protein on B-lymphocytes development was linked to the aberrant internalisation of BCR from the cell membrane, subsequently leading to abnormal phosphorylation of BCR-associated kinases. Further, by studying the case of unknown entities, the unexpected significance of FCHO1 protein and clathrin-mediated endocytosis during T-lymphocyte development and function in humans was revealed. The last paper delineates the lineage relationship between myeloid cells and T lymphocytes. Development of cellular barcoding experiments allowed to follow hematopoietic lineage decisions and to answer the query about the origin of thymic DC and the mechanisms of thymic progenitor commitment.B- und T-Lymphozyten stellen zwei wesentliche Komponenten des adaptiven Immunsystems dar. Beide Linien gehen aus hämatopoetischen Vorläuferzellen hervor, die sich im Knochenmark befinden. Obwohl die endgültige Festlegung und die Differenzierungsschritte in unterschiedlichen lymphatischen Organen stattfinden, weisen B—und T-Zellen bemerkenswerte Ähnlichkeiten auf. Beide nutzen Rag-Gene zur somatischen Rekombination von Genen, die für ihre Antigenerkennungsrezeptoren kodieren. Während B- und T-Zellen verschiedene Sets an Genen rekombinieren, erkennt der Rag1/Rag2-Gen-Komplex dasselbe kurze DNA-Motiv, um die Reaktion zu katalysieren. Des Weiteren sind ihre endgültigen Festlegungsprozesse und ihre Selektion der neu entstandenen Rezeptoren ähnlich und einzigartig. Die Abbildung des regulatorischen Netzwerks von Lymphozyten könnte auch als Modell angesehen werden, das es erlaubt, grundlegende Mechanismen der ncRNA-Wirkungsweise zu verstehen. Außerdem gestattet es, unser Verständnis der wesentlichen Prozesse zu vertiefen, in denen B- und T-Lymphozyten beteiligt sind. Die erste hier zusammengefasste Studie beschreibt den Einfluss der microRNA-191 auf das transkriptionelle Regulationsnetzwerk und die posttranskriptionelle Genregulation. Die Transkriptionsfaktoren FoxP1, E2A und Egr1 wurden als direkte nachgeschaltete Ziele von miR-191 identifiziert. Sowohl die Deletion als auch die ektopische Expression von miR-191 hatten einen Entwicklungsstillstand bei Zellen der B-Zelllinie zur Folge, was zeigt, dass die Feinabstimmung der kombinierten Expressionslevels von Foxp1, E2A und Egr1, die wiederum die somatische Rekombination und die zytokingesteuerte Expansion kontrollieren, eine Voraussetzung für eine effiziente B-Zellentwicklung darstellt. Zwei weitere Studien haben die molekularen Mechanismen von primären Immundefizienzen untersucht. Die zentrale Rolle des LAMTOR2 (p14)-Proteins in der Entwicklung von B-Lymphozyten wurde mit der aberranten Internalisierung des BCRs von der Zellmembran in Verbindung gebracht, die eine abnormale Phosphorylierung von BCR-assoziierten Kinasen zur Folge hat. Des Weiteren wurde durch die Untersuchung unbekannter Entitäten die unerwartete Bedeutung des FCHO1-Proteins und der Clathrin-vermittelten Endozytose für die Entwicklung und Funktion von T-Lymphozyten im Menschen aufgedeckt. Die letzte Veröffentlichung beschreibt die Abstammungsbeziehung von myeloiden Zellen und T-Lymphozyten. Die Etablierung von zellulären Barcodes erlaubte es, die Entscheidung der hämatopoetischen Abstammungslinie nachzuvollziehen und die Frage nach dem Ursprung von thymischen DCs, sowie den Mechanismen der Festlegung der Thymus-Vorläuferzellen zu beantworten

LAMTOR2 (p14) controls B cell differentiation by orchestrating endosomal BCR trafficking

B-cell development and function depend on stage-specific signaling through the B-cell antigen receptor (BCR). Signaling and intracellular trafficking of the BCR are connected, but the molecular mechanisms of this link are incompletely understood. Here, we investigated the role of the endosomal adaptor protein and member of the LAMTOR/Ragulator complex LAMTOR2 (p14) in B-cell development. Efficient conditional deletion of LAMTOR2 at the pre-B1 stage using mb1-Cre mice resulted in complete developmental arrest. Deletion of LAMTOR2 using Cd19-Cre mice permitted analysis of residual B cells at later developmental stages, revealing that LAMTOR2 was critical for the generation and activation of mature B lymphocytes. Loss of LAMTOR2 resulted in aberrant BCR signaling due to delayed receptor internalization and endosomal trafficking. In conclusion, we identify LAMTOR2 as critical regulator of BCR trafficking and signaling that is essential for early B-cell development in mice

Thymic γδ T cells in the absence of miR-181a/b-1.

<p>(A) Expression analysis of miR-181a in FACS-sorted thymocytes pooled from 5 adult or 8 neonatal TcrdH2BeGFP mice. Expression levels of the indicated cell populations were analyzed by quantitative RT-PCR and normalized to snoRNA 412. Error bars show range of relative expression levels from triplicates. (B) Bar graph shows absolute γδ T cell numbers in miR-181a/b-1^–/–x TcrdH2BeGFP mice (–/–) compared to TcrdH2BeGFP and miR-181a/b-1^+/–x TcrdH2BeGFP controls (ctrl.), pooled data from five independent experiments with each 2–5 mice per group, mean + SD. (C) Expression analysis of miR-181d in FACS-sorted thymocytes pooled from 5 miR-181a/b-1^–/–x TcrdH2BeGFP mice (–/–) and TcrdH2BeGFP controls (ctrl.). One representative experiment of two independent experiments that gave similar results. Expression levels of the indicated cell populations were analyzed by quantitative RT-PCR and normalized to snoRNA 412. Error bars show range of relative expression levels from triplicates. (D–I) FACS analysis of thymic γδ T cells in–/–mice compared to ctrl mice (D, F-I) and mixed bone marrow chimeras (E). (D) Vγ usage of thymic γδ T cells (gated on Tcrβ^–GFP^hi cells). Scatter plot shows pooled data from five experiments with 3–6 mice per group, one dot represents one mouse, mean. (E) Flow cytometric analysis of 1:1 mixed bone marrow chimeras. Scatter plot shows ratios of miR-181a/b-1^–/–(KO) and miR-181a/b-1 sufficient wild type (WT) donor Vγ1⁺ and Vγ4⁺ cells among all lymphocytes, respectively. Data are pooled from two independent experiments with each 3 mice per group, harmonic mean. (F) Scatter plot shows absolute numbers of NK1.1⁺ cells, pooled data from five independent experiments with each 2–5 mice per group. (G) Scatter plot shows absolute numbers of NK1.1⁺ γδ T cells, pooled data from five independent experiments with each 2–5 mice per group. (H) Representative contour plots of cluster B (CD44^hiCD24^–) and cluster A (CD44^–/loCD24⁺) γδ thymocytes (gated on Tcrβ^–GFP^hi cells), numbers indicate mean +/–SD of pooled data from four independent experiments with each 2–5 mice per group. (I) Representative contour plots of CCR6⁺ and NK1.1⁺ cluster B cells, numbers indicate mean +/–SD of pooled data from four independent experiments with each 2–6 mice per group. Statistical analyses were performed using the Mann-Whitney test.</p

Unchanged peripheral lymph node γδ T cell compartment in the absence of miR-181a/b-1.

<p>FACS analysis of γδ T cells in pLN of miR-181a/b-1^–/–x TcrdH2BeGFP mice (–/–) compared to miR-181a/b-1 sufficient controls, TcrdH2BeGFP and miR-181a/b-1^+/–x TcrdH2BeGFP mice (here referred to as ctrl.). (A) Total γδ T cells numbers in pLN of the indicated phenotypes. Scatter plot shows pooled data from five independent experiment with n = 2–5 mice per group, mean. (B) Scatter plot shows absolute numbers of NK1.1⁺ γδ T cells, pooled data from five independent experiments with each 2–5 mice per group, mean. (C) Vγ usage of γδ T cells (gated on Tcrβ^–GFP^hi cells). Bar graph shows pooled data from 5 experiments with 3–6 mice per group, mean + SD. (D + E) Intracellular cytokine staining for IFN-γ and IL-17A gated on γδ T cells. (D) Representative contour plots of two independent experiments with similar outcome, with each n = 2–5 mice per group. Numbers indicate mean +/–SD from pooled data. (E) Bar gaph shows pooled data from the two independent experiments, mean + SD. Statistical analyses were performed using the Mann-Whitney test.</p