The study of neurodevelopmental molecular mechanisms in schizophrenia requires the development of adequate biological models such as patient-derived cells and their derivatives. We previously ...utilized cell lines with neural progenitor properties (CNON) derived from the superior or middle turbinates of patients with schizophrenia and control groups to study schizophrenia-specific gene expression. In this study, we analyzed single-cell RNA seq data from two CNON cell lines (one derived from an individual with schizophrenia (SCZ) and the other from a control group) and two biopsy samples from the middle turbinate (MT) (also from an individual with SCZ and a control). We compared our data with previously published data regarding the olfactory neuroepithelium and demonstrated that CNON originated from a single cell type present both in middle turbinate and the olfactory neuroepithelium and expressed in multiple markers of mesenchymal cells. To define the relatedness of CNON to the developing human brain, we also compared CNON datasets with scRNA-seq data derived from an embryonic brain and found that the expression profile of the CNON closely matched the expression profile one of the cell types in the embryonic brain. Finally, we evaluated the differences between SCZ and control samples to assess the utility and potential benefits of using CNON single-cell RNA seq to study the etiology of schizophrenia.
Cell membrane phosphatidylcholine (PC) composition is regulated by lysophosphatidylcholine acyltransferase (LPCAT); changes in membrane PC saturation are implicated in metabolic disorders. Here, we ...identified LPCAT3 as the major isoform of LPCAT in adipose tissue and created adipocyte-specific Lpcat3-knockout mice to study adipose tissue lipid metabolism. Transcriptome sequencing and plasma adipokine profiling were used to investigate how LPCAT3 regulates adipose tissue insulin signaling. LPCAT3 deficiency reduced polyunsaturated PCs in adipocyte plasma membranes, increasing insulin sensitivity. LPCAT3 deficiency influenced membrane lipid rafts, which activated insulin receptors and AKT in adipose tissue, and attenuated diet-induced insulin resistance. Conversely, higher LPCAT3 activity in adipose tissue from ob/ob, db/db, and high-fat diet-fed mice reduced insulin signaling. Adding polyunsaturated PCs to mature human or mouse adipocytes in vitro worsened insulin signaling. We suggest that targeting LPCAT3 in adipose tissue to manipulate membrane phospholipid saturation is a new strategy to treat insulin resistance.
Objective
Single‐cell RNA‐sequencing of middle turbinate mucosa was performed to create the first single‐cell transcriptome catalog of this part of the human body.
Study Design
Basic science ...research.
Setting
Single center, tertiary care center.
Methods
Samples were obtained from the head of the middle turbinate from a healthy volunteer. After the specimen was prepared per lab protocol, cells were dissociated, resuspended, and counted. Single‐cell libraries were then prepared according to the 10x Genomics protocol and sequenced using NovaSeq 6000 (Illumina). Sequencing data were processed using Cell Ranger, and clustering and gene expression analysis was performed using Seurat. Cell types were annotated through expression profiling of single cells using known markers and data from other single‐cell studies.
Results
Fourteen unique cell types were identified, including serous, goblet, club, basal, ciliated, endothelial, and mesenchymal cells, as well as multiple types of blood cells.
Conclusion
This catalog provides a comprehensive depiction of the cellular composition of middle turbinate mucosa. By uncovering the cellular stratification of gene expression profiles in the healthy middle turbinate epithelium, the groundwork has been laid for further investigation into the molecular pathogenesis and targeted therapy of sinonasal disease.
•DFG-5 α-1,6-mannase associates with cell wall glycoproteins. This association is dependent upon N-linked galactomannans.•DFG-5 recognizes the α-1,6-backbone of the N-linked galactomannans and has ...enzymatic activity.•DFG-5 discriminates between cell wall glycoproteins and secreted glycoproteins.•By cleaving the N-linked galactomannans on cell wall glycoproteins, DFG-5 targets them for incorporation into the cell wall.•Secreted glycoproteins are not recognized by DFG-5 and are released into the growth medium.
The formation of a cell wall is vital for the survival and growth of a fungal cell. Fungi express members of the GH76 family of α-1,6-mannanases which play an important role in cell wall biogenesis. In this report we characterize the Neurospora crassa DFG-5 α-1,6-mannanase and demonstrate that it binds to the α-1,6-mannose backbone of an N-linked galactomannan found on cell wall glycoproteins. We show that DFG-5 has an enzymatic activity and provide evidence that it processes the α-1,6-mannose backbone of the N-linked galactomannan. Site-directed mutagenesis and complementation experiments show that D116 and D117 are located at the DFG-5 active site. D76 and E130, which are located in a groove on the opposite side of the protein, are also important for enzyme function. Cell wall glycoproteins co-purify with DFG-5 demonstrating a specific association between DFG-5 and cell wall glycoproteins. DFG-5 is able to discriminate between cell wall and secreted glycoproteins, and does not bind to the N-linked galactomannans present on secreted glycoproteins. DFG-5 plays a key role in targeting extracellular glycoproteins to their final destinations. By processing the galactomannans on cell wall proteins, DFG-5 targets them for cell wall incorporation by lichenin transferases. The N-linked galactomannans on secreted proteins are not processed by DFG-5, which targets these proteins for release into the extracellular medium.
