TY - JOUR AB - Hyperpolarization-activated cyclic-nucleotide-gated (HCN) channels control electrical rhythmicity and excitability in the heart and brain, but the function of HCN channels at the subcellular level in axons remains poorly understood. Here, we show that the action potential conduction velocity in both myelinated and unmyelinated central axons can be bidirectionally modulated by a HCN channel blocker, cyclic adenosine monophosphate (cAMP), and neuromodulators. Recordings from mouse cerebellar mossy fiber boutons show that HCN channels ensure reliable high-frequency firing and are strongly modulated by cAMP (EC50 40 mM; estimated endogenous cAMP concentration 13 mM). In addition, immunogold-electron microscopy revealed HCN2 as the dominating subunit in cerebellar mossy fibers. Computational modeling indicated that HCN2 channels control conduction velocity primarily by altering the resting membrane potential and are associated with significant metabolic costs. These results suggest that the cAMP-HCN pathway provides neuromodulators with an opportunity to finely tune energy consumption and temporal delays across axons in the brain. AU - Byczkowicz, Niklas AU - Eshra, Abdelmoneim AU - Montanaro-Punzengruber, Jacqueline-Claire AU - Trevisiol, Andrea AU - Hirrlinger, Johannes AU - Kole, Maarten Hp AU - Shigemoto, Ryuichi AU - Hallermann, Stefan ID - 6868 JF - eLife TI - HCN channel-mediated neuromodulation can control action potential velocity and fidelity in central axons VL - 8 ER - TY - JOUR AB - The apical hook is a transiently formed structure that plays a protective role when the germinating seedling penetrates through the soil towards the surface. Crucial for proper bending is the local auxin maxima, which defines the concave (inner) side of the hook curvature. As no sign of asymmetric auxin distribution has been reported in embryonic hypocotyls prior to hook formation, the question of how auxin asymmetry is established in the early phases of seedling germination remains largely unanswered. Here, we analyzed the auxin distribution and expression of PIN auxin efflux carriers from early phases of germination, and show that bending of the root in response to gravity is the crucial initial cue that governs the hypocotyl bending required for apical hook formation. Importantly, polar auxin transport machinery is established gradually after germination starts as a result of tight root-hypocotyl interaction and a proper balance between abscisic acid and gibberellins. AU - Zhu, Qiang AU - Gallemi, Marçal AU - Pospíšil, Jiří AU - Žádníková, Petra AU - Strnad, Miroslav AU - Benková, Eva ID - 6897 IS - 17 JF - Development TI - Root gravity response module guides differential growth determining both root bending and apical hook formation in Arabidopsis VL - 146 ER - TY - JOUR AB - Until recently, a great amount of brain studies have been conducted in human post mortem tissues, cell lines and model organisms. These researches provided useful insights regarding cell-cell interactions occurring in the brain. However, such approaches suffer from technical limitations and inaccurate modeling of the tissue 3D cytoarchitecture. Importantly, they might lack a human genetic background essential for disease modeling. With the development of protocols to generate human cerebral organoids, we are now closer to reproducing the early stages of human brain development in vitro. As a result, more relevant cell-cell interaction studies can be conducted. In this review, we discuss the advantages of 3D cultures over 2D in modulating brain cell-cell interactions during physiological and pathological development, as well as the progress made in developing organoids in which neurons, macroglia, microglia and vascularization are present. Finally, we debate the limitations of those models and possible future directions. AU - Oliveira, Bárbara AU - Yahya, Aysan Çerağ AU - Novarino, Gaia ID - 6896 JF - Brain Research SN - 00068993 TI - Modeling cell-cell interactions in the brain using cerebral organoids VL - 1724 ER - TY - GEN AB - OGs with putative pseudogenes by the number of affected genomes in different chlamydial species. Frameshift and nonsense mutations located less than 60 bp upstreamof the gene end or present in a single genome from the corresponding OG were excluded. (CSV 31 kb) AU - Sigalova, Olga AU - Chaplin, Andrei AU - Bochkareva, Olga AU - Shelyakin, Pavel AU - Filaretov, Vsevolod AU - Akkuratov, Evgeny AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9731 TI - Additional file 11 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Predicted frameshift and nonsense mutations in Chlamydial pan-genome. For the analysis of putative pseudogenes, events located less than 60 bp. away from gene end or present in a single genome from the corresponding OG were excluded. (CSV 600 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V. AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9783 TI - Additional file 10 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Frameshift and nonsense mutations near homopolymeric tracts of OG1 genes. Only 374 genes with typical length and domain composition were considered. (CSV 6 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V. AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9897 TI - Additional file 20 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Distribution of OGs with mosaic phyletic patterns across species (complete genomes only). (CSV 7 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V. AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9890 TI - Additional file 15 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Distribution of OGs with mosaic phyletic patterns across species (all genomes). (CSV 10 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9892 TI - Additional file 16 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Summary of peripheral genesa phyletic patterns and tree concordance. (CSV 26 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V. AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9893 TI - Additional file 17 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER - TY - GEN AB - Orthologous families (OFs) derived by MCL clustering of OGs. (CSV 189 kb) AU - Sigalova, Olga M. AU - Chaplin, Andrei V. AU - Bochkareva, Olga AU - Shelyakin, Pavel V. AU - Filaretov, Vsevolod A. AU - Akkuratov, Evgeny E. AU - Burskaia, Valentina AU - Gelfand, Mikhail S. ID - 9894 TI - Additional file 18 of Chlamydia pan-genomic analysis reveals balance between host adaptation and selective pressure to genome reduction ER -