Transcriptional landscape of epithelial and immune cell populations revealed through FACS-seq of healthy human skin.

Human skin consists of multiple cell types, including epithelial, immune, and stromal cells. Transcriptomic analyses have previously been performed from bulk skin samples or from epithelial and immune cells expanded in cell culture. However, transcriptomic analysis of bulk skin tends to drown out expression signals from relatively rare cells while cell culture methods may significantly alter cellular phenotypes and gene expression profiles. To identify distinct transcriptomic profiles of multiple cell populations without substantially altering cell phenotypes, we employed a fluorescence activated cell sorting method to isolate keratinocytes, dendritic cells, CD4+ T effector cells, and CD8+ T effector cells from healthy skin samples, followed by RNA-seq of each cell population. Principal components analysis revealed distinct clustering of cell types across samples, while differential expression and coexpression network analyses revealed transcriptional profiles of individual cell populations distinct from bulk skin, most strikingly in the least abundant CD8+ T effector population. Our work provides a high resolution view of cutaneous cellular gene expression and suggests that transcriptomic profiling of bulk skin may inadequately capture the contribution of less abundant cell types

Transcriptome analysis of cortical tissue reveals shared sets of downregulated genes in autism and schizophrenia.

Autism (AUT), schizophrenia (SCZ) and bipolar disorder (BPD) are three highly heritable neuropsychiatric conditions. Clinical similarities and genetic overlap between the three disorders have been reported; however, the causes and the downstream effects of this overlap remain elusive. By analyzing transcriptomic RNA-sequencing data generated from post-mortem cortical brain tissues from AUT, SCZ, BPD and control subjects, we have begun to characterize the extent of gene expression overlap between these disorders. We report that the AUT and SCZ transcriptomes are significantly correlated (P<0.001), whereas the other two cross-disorder comparisons (AUT-BPD and SCZ-BPD) are not. Among AUT and SCZ, we find that the genes differentially expressed across disorders are involved in neurotransmission and synapse regulation. Despite the lack of global transcriptomic overlap across all three disorders, we highlight two genes, IQSEC3 and COPS7A, which are significantly downregulated compared with controls across all three disorders, suggesting either shared etiology or compensatory changes across these neuropsychiatric conditions. Finally, we tested for enrichment of genes differentially expressed across disorders in genetic association signals in AUT, SCZ or BPD, reporting lack of signal in any of the previously published genome-wide association study (GWAS). Together, these studies highlight the importance of examining gene expression from the primary tissue involved in neuropsychiatric conditions-the cortical brain. We identify a shared role for altered neurotransmission and synapse regulation in AUT and SCZ, in addition to two genes that may more generally contribute to neurodevelopmental and neuropsychiatric conditions

Transcriptional and translational differences of microglia from male and female brains

Sex differences in brain structure and function are of substantial scientific interest because of sex-related susceptibility to psychiatric and neurological disorders. Neuroinflammation is a common denominator of many of these diseases and thus microglia as the brain ́s immunocompetent cells has come into focus in sex specific studies. Here we show differences in structure, function, transcriptomic and proteomic profile in microglia freshly isolated from male and female mouse brains. We show that male microglia are more frequent in specific brain areas, have a higher antigen presenting capacity, and appear to have a higher potential to respond to stimuli such as ATP reflected in higher baseline outward and inward currents and higher protein expression of purinergic receptors. Altogether, we provide a comprehensive resource to generate and validate hypotheses regarding brain sex differences that may support anticipated gender-based therapeutic strategies in the future.Aufgrund von geschlechtsspezifischen Ausprägungen von psychiatrischen und neurologischen Erkrankungen ist es von großer Wichtigkeit Unterschiede zwischen weiblichen und männlichen Gehirnstrukturen und ihren Funktionen zu untersuchen. Entzündungen im zentralen Nervensystem sind der gemeinsame Nenner von vielen dieser Krankheiten. Mikroglia als die immunkompetenten Zellen des Gehirns sind daher in den Fokus von geschlechtsspezifischen Studien gerückt. In meiner Arbeit zeige ich Unterschiede in Struktur und Funktion und im Transkriptom und Proteom Profil von Mikroglia aus frisch isolierten männlichen und weiblichen Mausgehirnen. Ich zeige, dass männliche Mikroglia in bestimmten Hirnregionen eine höhere Dichte aufweisen, eine größere Kapazität besitzen Antigene zu präsentieren und ein höheres Potential zeigen, auf Stimuli wie zum Beispiel ATP zu reagieren. Dies wird durch stärkere Auswärts- und Einwärtsströme über die Zellmembran unter normal Bedingungen und einer höheren Expression von purinergen Rezeptoren reflektiert. Ich stelle in dieser Arbeit umfangreiche Ressourcen bereit, um Hypothesen zu generieren und zu validieren, die sich mit Unterschieden zwischen weiblichen und männlichen Gehirnen und insbesondere Mikroglia befassen. Dies könnte für mögliche zukünftige geschlechtsbasierte therapeutische Ansätze eine unschätzbare Hilfe sein

A transcriptomic investigation of handicap models in sexual selection

We are grateful to D. Calder and T. Helps for access to study sites, and G. Murray-Dickson and M. Oliver for help with fieldwork and comments on manuscript drafts. This work was funded by NERC grant NE/D000602/1 (SBP), a NERC advanced fellowship (FM) and a BBSRC studentship (MAW)Peer reviewedPostprin

Diversity of immunoglobulin light chain genes in non-teleost ray-finned fish uncovers IgL subdivision into five ancient isotypes

<p>The aim of this study was to fill important gaps in the evolutionary history of immunoglobulins by examining the structure and diversity of IgL genes in non-teleost ray-finned fish. First, based on the bioinformatic analysis of recent transcriptomic and genomic resources, we experimentally characterized the IgL genes in the chondrostean fish, Acipenser ruthenus (sterlet). We show that this species has three loci encoding IgL kappa-like chains with a translocon-type gene organization and a single VJC cluster, encoding homogeneous lambda-like light chain. In addition, sterlet possesses sigma-like VL and J-CL genes, which are transcribed separately and both encode protein products with cleavable leader peptides. The Acipenseriformes IgL dataset was extended by the sequences mined in the databases of species belonging to other non-teleost lineages of ray-finned fish: Holostei and Polypteriformes. Inclusion of these new data into phylogenetic analysis showed a clear subdivision of IgL chains into five groups. The isotype described previously as the teleostean IgL lambda turned out to be a kappa and lambda chain paralog that emerged before the radiation of ray-finned fish. We designate this isotype as lambda-2. The phylogeny also showed that sigma-2 IgL chains initially regarded as specific for cartilaginous fish are present in holosteans, polypterids, and even in turtles. We conclude that there were five ancient IgL isotypes, which evolved differentially in various lineages of jawed vertebrates.</p