Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.
Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.
Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.
Project description:Chytrids are early-diverging fungi that share features with animals that have been lost in most other fungi. They hold promise as a system to study fungal and animal evolution, but we lack genetic tools for hypothesis testing. Here, we generated transgenic lines of the chytrid Spizellomyces punctatus, and used fluorescence microscopy to explore chytrid cell biology and development during its life cycle. We show that the chytrid undergoes multiple rounds of synchronous nuclear division, followed by cellularization, to create and release many daughter 'zoospores'. The zoospores, akin to animal cells, crawl using actin-mediated cell migration. After forming a cell wall, polymerized actin reorganizes into fungal-like cortical patches and cables that extend into hyphal-like structures. Actin perinuclear shells form each cell cycle and polygonal territories emerge during cellularization. This work makes Spizellomyces a genetically tractable model for comparative cell biology and understanding the evolution of fungi and early eukaryotes.
Project description:Chytrid fungi play key ecological roles in aquatic ecosystems, and some species cause a devastating skin disease in frogs and salamanders. Additionally, chytrids occupy a unique phylogenetic position- sister to the well-studied Dikarya (the group including yeasts, sac fungi, and mushrooms) and related to animals- making chytrids useful for answering important evolutionary questions. Despite their importance, little is known about the basic cell biology of chytrids. A major barrier to understanding chytrid biology has been a lack of genetic tools with which to test molecular hypotheses. Medina and colleagues recently developed a protocol for Agrobacterium -mediated transformation of Spizellomyces punctatus. In this manuscript, we describe the general procedure including planning steps and expected results. We also provide in-depth, step-by-step protocols and video guides for performing the entirety of this transformation procedure on protocols.io (dx.doi.org/10.17504/protocols.io.x54v9dd1pg3e/v1).
Project description:BACKGROUND: Human SP-A1 and SP-A2, encoded by SFTPA1 and SFTPA2 and their genetic variants differentially impact alveolar macrophage (AM) functions and regulation, including the miRNome. We investigated whether miRNome differences previously observed between AM from SP-A2 and SP-A1/SP-A2 mice are due to continued qualitative differences or a delayed response of mice carrying a single gene. METHODS: Human transgenic (hTG) mice, carrying SP-A2 or both SP-A genes and SP-A-KO mice were exposed to filtered air (FA) or O3. AM miRNA levels, target gene expression and pathways determined 18 h after O3 exposure. RESULTS: We found: (a) Differences in miRNome due to sex, SP-A genotype, and exposure; (b) miRNome of both sexes was largely downregulated by O3 ; co-ex had fewer changed (≥2X) miRNAs than either group. (c) the number and direction of expression of genes with significant changes in males and females in co-ex is almost the opposite of those in SP-A2; (iv) The same pathways were found in the studied groups; (e) O3 exposure attenuated sex differences; a higher number of genotype-dependent and genotype-independent miRNAs was common in both sexes after O3 exposure. CONCLUSION: Qualitative differences between SP-A2 and co-ex persist 18 h post-O3, and O3 attenuates sex differences.