Structural differences of cell walls in earlywood and latewood of Pinus sylvestris and their contribution to biomass recalcitrance

Scots pine (Pinus sylvestris L.) is an evergreen coniferous tree with wide distribution and good growth performance in a range of habitats. Therefore, wood from P. sylvestris is produced in many managed forests and is frequently used in industry. Despite the importance of pine wood, we still do not fully understand its molecular structure what limits improvements in its processing. One of the basic features leading to variation in wood properties is the presence of earlywood and latewood which form annual growth rings. Here, we characterise biochemical traits that differentiate cell walls of earlywood and latewood in Scots pine. We discover that latewood is less recalcitrant to enzymatic digestion, with galactoglucomannan showing particularly pronounced difference in accessibility. Interestingly, characterisation of lignin reveals a higher proportion of coniferaldehydes in pine latewood and suggests the presence of a different linkage landscape in this wood type. With complementary analysis of wood polysaccharides this enabled us to propose the first detailed molecular model of earlywood and latewood and to conclude that the variation in lignin structure is likely the main determinant of differences in recalcitrance observed between the two wood types in pine. Our discoveries lay the foundation for improvements in industrial processes that use pine wood since we show clear pathways for increasing the efficiency of enzymatic processing of this renewable material. Our work will help guide future breeding of pine trees with desired timber properties and can help link molecular structure of softwood cell walls to function of the different types of xylem in conifers

Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils

Plant biomass plays an increasingly important role in the circular bioeconomy, replacing non-renewable fossil resources. Genetic engineering of this lignocellulosic biomass could benefit biorefinery transformation chains by lowering economic and technological barriers to industrial processing. However, previous efforts have mostly targeted the major constituents of woody biomass: cellulose, hemicellulose and lignin. Here we report the engineering of wood structure through the introduction of callose, a polysaccharide novel to most secondary cell walls. Our multiscale analysis of genetically engineered poplar trees shows that callose deposition modulates cell wall porosity, water and lignin contents and increases the lignin-cellulose distance, ultimately resulting in substantially decreased biomass recalcitrance. We provide a model of the wood cell wall nano-architecture engineered to accommodate the hydrated callose inclusions. Ectopic polymer introduction into biomass manifests in new physico-chemical properties and offers new avenues when considering lignocellulose engineering.Bourdon et al. demonstrate the possibility to ectopically synthesize callose, a polymer restricted to primary cell walls, into Arabidopsis and aspen secondary cell walls to manipulate their ultrastructure and ultimately reduce their recalcitrance

PTEN as a Prognostic and Predictive Marker in Postoperative Radiotherapy for Squamous Cell Cancer of the Head and Neck

BACKGROUND: Tumor suppressor PTEN is known to control a variety of processes related to cell survival, proliferation, and growth. PTEN expression is considered as a prognostic factor in some human neoplasms like breast, prostate, and thyroid cancer. METHODOLOGY/PRINCIPAL FINDINGS: In this study we analyzed the influence of PTEN expression on the outcome of a randomized clinical trial of conventional versus 7-days-a-week postoperative radiotherapy for squamous cell cancer of the head and neck. The patients with cancer of the oral cavity, oropharynx, and larynx were randomized to receive 63 Gy in fractions of 1.8 Gy given 5 days a week (CF) or 7 days a week (p-CAIR). Out of 279 patients enrolled in the study, 147 paraffin blocks were available for an immunohistochemical assessment of PTEN. To evaluate the prognostic value of PTEN expression and the effect of fractionation relative to PTEN, the data on the outcome of a randomized clinical trial were analyzed. Tumors with a high intensity of PTEN staining had significant gain in the loco-regional control (LRC) from p-CAIR (5-year LRC 92.7% vs. 70.8%, for p-CAIR vs. CF, p = 0.016, RR = 0.26). By contrast, tumors with low intensity of PTEN did not gain from p-CAIR (5-year LRC 56.2% vs. 47.2%, p = 0.49, RR = 0.94). The intensity of PTEN highly affected the LRC in a whole group of 147 patients (5-year LRC 80.9% vs. 52.3% for high vs. low PTEN, p = 0.0007, RR = 0.32). In multivariate Cox analysis, including neck node involvement, EGFR, nm23, Ki-67, p53, cyclin D1, tumor site and margins, PTEN remained an independent predictor of LRC (RR = 2.8 p = 0.004). CONCLUSIONS/SIGNIFICANCE: These results suggest that PTEN may serve as a potent prognostic and predictive marker in postoperative radiotherapy for high-risk squamous cell cancer of the head and neck

Editorial Censorship in the Russian Partition in the 19th century

The article provides an insight into the problem of editorial censorship in the Kingdom of Poland. It shows that the nature of the censorship measures did not only depend on the attitude towards the state system, but also on the in-house relations dictated by the policy of the publisher and market relations. The editor, representing both private and corporate interests, imposes changes of a censorious nature not only under political or moral pressure, but also under the publisher’s pressure. And thus, he becomes a censor. This provides an additional insight into the practice of censorship under the Partitions of Poland. This issue is commonly viewed from the national and patriotic perspective that neglects this aspect, emphasising mainly the external oppression of the partitioning powers. In order to illustrate the differences between the various publishing policies, the measures applied by the editors of Przegląd Tygodniowy and Tygodnik Ilustrowany weeklies are discussed

Determine the metastatic rate of 4T1 breast cancer in the BALB/c mouse model; immunofluorescence analysis of lymph nodes

Węzły chłonne, tworzące część układu limfatycznego, są niezwykle istotne dla odpowiedzi immunologicznej stanowiąc środowisko, w obrębie którego mogą kontaktować się antygeny i komórki limfoidalne. W odpowiedzi na inwazyjny nowotwór, limfocyty zebrane w węźle ulegają aktywacji zmieniając strukturę organu. Zastosowany w niniejszej pracy model nowotworu 4T1 tworzy guz piersi, wykazujący wiele cech pokrewnych z ludzkim rozwojem choroby. Przerzutuje do wielu tkanek w organizmie, w tym do węzłów chłonnych i płuc. Obecność komórek nowotworowych w węzłach jest jednym z kluczowych elementów determinujących stadium choroby i określających dalsze postępowanie kliniczne. Celem pracy było określenie tempa przerzutowania raka piersi 4T1 w mysim modelu BALB/c z wykorzystaniem analizy immunofluorescencyjnej i morfometrycznej. Otrzymane wyniki wskazują pozytywną korelację pomiędzy wielkością prawostronnych węzłów chłonnych (znajdujących się po stronie zajętej przez nowotwór), a rozwojem guza pierwotnego. Barwienie immunofluorescencyjne potwierdza obecność metasaz 4T1 w węzłach chłonnych, zarówno pachwinowych, jak i pachowych. Jednocześnie przeprowadzona analiza liczby widocznych makroskopowo przerzutów na płucach, jak również masy płuc i śledziony pozwoliła na określenie momentu, w którym guz zaczyna przeistaczać się w inwazyjną formę.Lymph nodes, which form the part of the lymphatic system are extremely important for the immune response. They create the environment in which antigens and lymphoid cells can interact. In response to invasive tumors, lymphocytes collected in the nodule are activated and altering the organ structure. The 4T1 tumor model used in this study creates a breast tumor with many related features to human disease. It metastasizes to different tissues in the body, including the lymph nodes and lungs. The presence of tumor cells in lymph nodes is one of the key determinants of disease progression and further clinical progress.The goal of this study was to determine the rate of 4T1 breast cancer metastasis in murine BALB/ c model using immunofluorescence and morphometric analysis. Obtained results indicate a positive correlation between the size of the right-side lymph nodes (on the side of the tumor) and the kinetic of growth ofthe primary tumor. Immunofluorescence staining confirms the presence of 4T1 metasases in the lymph nodes, both linguinal and axillary. Simultaneously analysis of the number of macroscopically visible lung metastases, as well as lung and spleen masses, determined the time at which the tumor began to transform into an invasive form

The Role of GLRs in the Arabidopsis thaliana Cellular Responses

Kanały GLR (ang. Glutamate receptor-like) są roślinnymi homologami jonotropowych receptorów zwierzęcych bramkowanych ligandem (iGluRs). iGluRs występują w centralnym systemie nerwowym, a ich dysfunkcja związana jest z rozwojem chorób neurodegeneracyjnych. Receptory zwierzęce w zależności od specyficznego agonisty można podzielić na receptory typu NMDA oraz typu AMPA. Arabidopsis thaliana posiada 20 genów kodujących podjednostki GLR. Ich rola w roślinach nie jest dokładnie poznana, ale najczęściej bada się je w kontekście przepuszczalności dla jonów Ca2+. Jony te są zaangażowane w regulacje wielu procesów komórkowych, w tym reorganizację cytoszkieletu aktynowego poprzez bezpośredni i pośredni wpływ na filamenty aktynowe.Przeprowadzone w pracy badania miały na celu sprawdzenie, czy w przypadku kanałów GLR możemy również zastosować podział na AMPA i NMDA. Zastosowanie specyficznych inhibitorów (CNQX – antagonista AMPA oraz MK-801 – antagonista NMDA) i histydyny jako agonisty pozwoliło na badanie: stężenia wapnia, reorganizacji cytoszkieletu aktynowego, wzrostu oraz odpowiedzi fototropicznej siewki. Podjęto również próbę wyznakowania kanałów GLR dostępnymi przeciwciałami anty NMDA. Uzyskane wyniki wskazują na zaangażowanie GLR we wzrost siewki zależny od warunków świetlnych oraz organu. We wzrost fototropiczny etiolowanych siewek zaangażowane są inne niż GLR kanały wapniowe. Rola GLR w pozostałych procesach wciąż pozostaje niewyjaśniona.Z uwagi na zaangażowanie GLR w odpowiedź rośliny na stres biotyczny i abiotyczny badanie ich funkcji i regulacji jest jednym z kluczowych zagadnień współczesnej agrobiotechnologiGLRs (Glutamate receptor-like) are plant homologues of animal ligand-gated ionotropic channels (iGluRs). iGluRs occur in the central nervous system and their dysfunction is associated with the development of neurodegenerative diseases. Animal receptors, depending on their specific agonist can be divided into NMDA type and AMPA type receptors. Arabidopsis thaliana possess 20 genes encoding GLR’s subunits. Their role in plants is not precisely understood, but they are most often studied in the context of permeability for Ca2+ ions. These ions are involved in the regulation of many cellular processes, including the reorganization of the actin cytoskeleton through direct and indirect effects on actin filaments.Conducted research in this thesis tried to establish whether in the case of GLR channels we can also divide them into AMPA and NMDA. The usage of specific inhibitors (CNQX - AMPA antagonist and MK-801 - NMDA antagonist) and histidine as agonists allowed the study of: calcium concentration, actin cytoskeleton reorganization, growth and phototropic seedling response. An attempt was also made to label GLR channels with available Anti-NMDA antibodies. The obtained results indicate the involvement of GLRs in seedling growth depending on the organ and light conditions. Phototropic growth of ethiolated seedlings involves calcium channels other than GLR. The role of GLRs in the other processes remains unexplained.Due to the involvement of GLRs in plant response to biotic and abiotic stress study of their function and regulation is one of the key issues of modern agrobiotechnology

Upregulation of GLRs expression by light in Arabidopsis leaves

BACKGROUND: Glutamate receptor-like (GLR) channels are plant homologs of iGluRs, animal ionotropic glutamate receptors which participate in neurotransmission. GLRs mediate plant adaptive processes and photomorphogenesis. Despite their contribution to light-dependent processes, signaling mechanisms that modulate GLR response to light remain unknown. Here we show that leaf expression of 7 out of 20 Arabidopsis GLRs is significantly up-regulated by monochromatic irradiation. RESULTS: Our data indicates that both red and blue light stimulate the expression of selected AtGLRs. Using a photosynthesis inhibitor and different irradiation regimes, we demonstrated that retrograde signaling from photosystem II is unlikely to be involved in light-dependent GLR up-regulation. Analysis of transcriptional patterns in mutants of key photoreceptors allowed us to observe that both phytochromes and cryptochromes are likely to be involved in the control of light-dependent up-regulation of AtGLR expression, with phytochromes playing a clearly dominating role in this process. CONCLUSIONS: In mature Arabidopsis leaves, phytochromes, assisted by cryptochromes, mediate light-driven transcriptional up-regulation of several genes encoding GLR proteins. Since GLRs are known to be involved in a wide range of plant developmental processes our results provide mechanistic insight into how light may influence plant growth and development. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12870-022-03535-7

Transformation of European ash (Fraxinus excelsior L.) callus as a starting point for understanding the molecular basis of ash dieback

The population of European ash (Fraxinus excelsior L.) is currently facing the risk of collapse, mainly due to ash dieback, a disease caused by a pathogenic fungus, Hymenoscyphus fraxineus. To facilitate studies into the molecular basis of ash dieback and design breeding strategies for a generation of resistant trees, it is necessary to develop tools enabling the study of gene function in F. excelsior. Despite this, a method for the genetic engineering of F. excelsior is still missing. Here, we report the first successful genetic transformation of F. excelsior callus and a selection process enabling the formation of stable transgenic callus lines. The protocol relies on the use of Agrobacterium tumefaciens to transform callus tissue derived from embryos of F. excelsior. In our experiments, we used the β-glucuronidase (GUS) reporter system to demonstrate the transformation of callus cells and performed RT-PCR experiments to confirm the stable expression of the transgene. Since ash dieback threatens the long-term stability of many native F. excelsior populations, we hope that the transformation techniques described in this manuscript will facilitate rapid progress in uncovering the molecular basis of the disease and the validation of gene targets previously proposed to be linked to the resistance of trees to H. fraxineus pathogenicity