Project description:Current spatial transcriptomics methods identify cell types and states in a spatial context but lack morphological information. Electron microscopy, in contrast, provides structural details at nanometer resolution without decoding the diverse cellular states and identity. STEM address this limitation by correlating multiplexed error-robust FISH with electron microscopy from adjacent tissue sections. Using STEM to characterize demyelinated lesions in mice, we were able to bridge spatially resolved transcriptional data with morphological information on cell identities. This approach allowed us to link the morphology of foamy microglia and interferon-response microglia with their transcriptional signatures.
Project description:We performed whole genome gene expression profiling in bronchial biopsies from PCD patients. We used the Quality Threshold clustering algorithm to identify groups of genes that revealed highly correlated RNA expression patterns in the biopsies. The largest cluster contained 372 genes and was significantly enriched for genes related to cilia. The database and literature search showed that 16250 genes in this cluster were known cilia genes, strongly indicating that the remaining 21022 genes were likely to be new cilia genes. The tissue expression pattern of the 210 new cilia genes and the 162 known genes was consistent with the presence of motile cilia in a given tissue. Analysis of the upstream promotor sequences revealed evidence for RFX transcription factors binding site motif in both subgroups. Total RNA obtained from 6 primary ciliary dyskinesia patients and 9 control individuals
Project description:Current spatial transcriptomics methods provide molecular and spatial information but no morphological readout. Here, we present STEM - a method that correlates multiplexed error-robust FISH with electron microscopy from neighboring tissue sections of the same sample. STEM links transcriptional and spatial organization of single cells with ultrastructural morphology of the tissue in vivo. Using STEM to characterize demyelinated white-matter lesions allowed us to link morphology of myelin-laden foamy microglia to transcriptional signature. Moreover, we revealed that interferon-response microglia have unique morphology and are enriched near CD8 T-cells.
Project description:To find and fuse with the egg, mammalian sperm must complete an arduous voyage through the female reproductive tract. This odyssey is powered by the sperm tail, a specialized motile cilium. Mammalian sperm tails are reinforced at the molecular scale with sperm-specific microtubule inner proteins (sperm-MIPs), but the identities of these sperm-MIPs are unknown. Here, we report high-resolution cryo-electron microscopy structures of bovine sperm doublet microtubules (DMTs), allowing us to identify many sperm-MIPs. We also resolve structures of singlet MTs in the endpiece, revealing MIPs shared between singlet and doublet MTs. We demonstrate that at least two sperm-MIPs bind and stabilize MTs in vitro. Our structures shed light on ciliary diversity across cell types and provide structural frameworks for understanding molecular underpinnings of male infertility
Project description:Approximately 80% of clinically clearly diagnosed patients suffering from primary ciliary dyskinesia (PCD) cannot be assigned to a specific gene defect. Despite extensive research on PCD and despite the increasing number of PCD genes and knowledge about their sites of action as e.g structural component or cytoplasmic pre-assembly factor, the biology of motile cilia and the pathomechanism leading to PCD is largely unknown. The aim of this study is to identify novel PCD related genes and processes relevant for motile cilia function.
We will perform exome sequencing, aiming on the analysis of family trios. In these families, the diagnosis of PCD is secured, but the underlying gene defects has so far not been identified.