TY - JOUR A1 - Kolora, Sree Rohit Raj A1 - Weigert, Anne A1 - Saffari, Amin A1 - Kehr, Stephanie A1 - Walter Costa, Maria Beatriz A1 - Spröer, Cathrin A1 - Indrischek, Henrike A1 - Chintalapati, Manjusha A1 - Lohse, Konrad A1 - Doose, Gero A1 - Overmann, Jörg A1 - Bunk, Boyke A1 - Bleidorn, Christoph A1 - Grimm-Seyfarth, Annegret A1 - Henle, Klaus A1 - Nowick, Katja A1 - Faria, Rui A1 - Stadler, Peter F. A1 - Schlegel, Martin T1 - Divergent evolution in the genomes of closely related lacertids, Lacerta viridis and L. bilineata, and implications for speciation JF - GigaScience N2 - Background Lacerta viridis and Lacerta bilineata are sister species of European green lizards (eastern and western clades, respectively) that, until recently, were grouped together as the L. viridis complex. Genetic incompatibilities were observed between lacertid populations through crossing experiments, which led to the delineation of two separate species within the L. viridis complex. The population history of these sister species and processes driving divergence are unknown. We constructed the first high-quality de novo genome assemblies for both L. viridis and L. bilineata through Illumina and PacBio sequencing, with annotation support provided from transcriptome sequencing of several tissues. To estimate gene flow between the two species and identify factors involved in reproductive isolation, we studied their evolutionary history, identified genomic rearrangements, detected signatures of selection on non-coding RNA, and on protein-coding genes. Findings Here we show that gene flow was primarily unidirectional from L. bilineata to L. viridis after their split at least 1.15 million years ago. We detected positive selection of the non-coding repertoire; mutations in transcription factors; accumulation of divergence through inversions; selection on genes involved in neural development, reproduction, and behavior, as well as in ultraviolet-response, possibly driven by sexual selection, whose contribution to reproductive isolation between these lacertid species needs to be further evaluated. Conclusion The combination of short and long sequence reads resulted in one of the most complete lizard genome assemblies. The characterization of a diverse array of genomic features provided valuable insights into the demographic history of divergence among European green lizards, as well as key species differences, some of which are candidates that could have played a role in speciation. In addition, our study generated valuable genomic resources that can be used to address conservation-related issues in lacertids. KW - sister species KW - PacBio and Illumina KW - de novo hybrid assembly KW - transcripts KW - noncoding RNA KW - zinc fingers KW - positive selection KW - UV response KW - inversions KW - gene flow Y1 - 2018 U6 - https://doi.org/10.1093/gigascience/giy160 SN - 2047-217X VL - 8 IS - 2 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Schneider, Rudolf A1 - Weigert, F. A1 - Lesnyak, V. A1 - Leubner, S. A1 - Lorenz, T. A1 - Behnke, Thomas A1 - Dubavik, A. A1 - Joswig, J. -O. A1 - Resch-Genger, U. A1 - Gaponik, N. A1 - Eychmueller, A. T1 - pH and concentration dependence of the optical properties of thiol-capped CdTe nanocrystals in water and D2O JF - Physical chemistry, chemical physics : a journal of European Chemical Societies N2 - The optical properties of semiconductor nanocrystals (SC NCs) are largely controlled by their size and surface chemistry, i.e., the chemical composition and thickness of inorganic passivation shells and the chemical nature and number of surface ligands as well as the strength of their bonds to surface atoms. The latter is particularly important for CdTe NCs, which – together with alloyed CdxHg1−xTe – are the only SC NCs that can be prepared in water in high quality without the need for an additional inorganic passivation shell. Aiming at a better understanding of the role of stabilizing ligands for the control of the application-relevant fluorescence features of SC NCs, we assessed the influence of two of the most commonly used monodentate thiol ligands, thioglycolic acid (TGA) and mercaptopropionic acid (MPA), on the colloidal stability, photoluminescence (PL) quantum yield (QY), and PL decay behavior of a set of CdTe NC colloids. As an indirect measure for the strength of the coordinative bond of the ligands to SC NC surface atoms, the influence of the pH (pD) and the concentration on the PL properties of these colloids was examined in water and D2O and compared to the results from previous dilution studies with a set of thiol-capped Cd1−xHgxTe SC NCs in D2O. As a prerequisite for these studies, the number of surface ligands was determined photometrically at different steps of purification after SC NC synthesis with Ellman's test. Our results demonstrate ligand control of the pH-dependent PL of these SC NCs, with MPA-stabilized CdTe NCs being less prone to luminescence quenching than TGA-capped ones. For both types of CdTe colloids, ligand desorption is more pronounced in H2O compared to D2O, underlining also the role of hydrogen bonding and solvent molecules. Y1 - 2016 U6 - https://doi.org/10.1039/c6cp03123d SN - 1463-9076 SN - 1463-9084 VL - 18 SP - 19083 EP - 19092 PB - Royal Society of Chemistry CY - Cambridge ER -