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Development (Cambridge, England) Nov 2023Histone-modifying proteins play important roles in the precise regulation of the transcriptional programs that coordinate development. KDM5 family proteins interact with...
Histone-modifying proteins play important roles in the precise regulation of the transcriptional programs that coordinate development. KDM5 family proteins interact with chromatin through demethylation of H3K4me3 as well as demethylase-independent mechanisms that remain less understood. To gain fundamental insights into the transcriptional activities of KDM5 proteins, we examined the essential roles of the single Drosophila Kdm5 ortholog during development. KDM5 performs crucial functions in the larval neuroendocrine prothoracic gland, providing a model to study its role in regulating key gene expression programs. Integrating genome binding and transcriptomic data, we identify that KDM5 regulates the expression of genes required for the function and maintenance of mitochondria, and we find that loss of KDM5 causes morphological changes to mitochondria. This is key to the developmental functions of KDM5, as expression of the mitochondrial biogenesis transcription factor Ets97D, homolog of GABPα, is able to suppress the altered mitochondrial morphology as well as the lethality of Kdm5 null animals. Together, these data establish KDM5-mediated cellular functions that are important for normal development and could contribute to KDM5-linked disorders when dysregulated.
Topics: Animals; Drosophila; Drosophila Proteins; Histone Demethylases; Chromatin; Biology
PubMed: 37800333
DOI: 10.1242/dev.202024 -
Development (Cambridge, England) Feb 2007An essential component of normal development is controlling the transition from cell proliferation to differentiation. One such transition occurs during Drosophila...
An essential component of normal development is controlling the transition from cell proliferation to differentiation. One such transition occurs during Drosophila oogenesis. In early oogenesis, germ cells undergo mitotic proliferation and contain a specialized organelle called a fusome, whereas later post-mitotic cells differentiate and lose the fusome as F-actin-rich ring canals form. The hts gene encodes the only Drosophila Adducin, and is a female-sterile mutant that affects both the fusome and ring canals. We show that one Hts protein, Ovhts, is a polyprotein that is cleaved to produce two products, Ovhts-Fus and Ovhts-RC. Whereas Ovhts-Fus localizes to the fusome in mitotic cells, Ovhts-RC localizes to ring canals throughout later oogenesis. We demonstrate that an uncleavable version of Ovhts delays the transition from fusome-containing cells to those that have ring canals. Ovhts is the first polyprotein shown to produce proteins that function in separate structures.
Topics: Actins; Animals; Calmodulin-Binding Proteins; Drosophila; Drosophila Proteins; Female; Multiprotein Complexes; Oocytes; Oogenesis; Ovary; Polyproteins
PubMed: 17215303
DOI: 10.1242/dev.02766 -
Advances in Experimental Medicine and... 2012Cell recognition requires interactions through molecules located on cell surface. The insect homolog of Down syndrome cell adhesion molecule (Dscam) manifests huge... (Review)
Review
Cell recognition requires interactions through molecules located on cell surface. The insect homolog of Down syndrome cell adhesion molecule (Dscam) manifests huge molecular diversity in its extracellular domain. High-affinity Dscam-Dscam interactions only occur between isoforms that carry identical extracellular domains. Homophilic Dscam signaling can, thus, vary in strength depending on the compositions of Dscams present on the opposing cell surfaces. Dscam abundantly exists in the developing nervous system and governs arborization and proper elaboration of neurites. Notably, individual neurons may stochastically and dynamically express a small subset of Dscam isoforms such that any given neurite can be endowed with a unique repertoire of Dscams. This allows individual neurites to recognize their sister branches. Self-recognition leads to self-repulsion, ensuring divergent migration of sister processes. By contrast, weak homophilic Dscam interactions may promote fasciculation of neurites that express analogous, but not identical, Dscams. Differential Dscam binding may provide graded cell recognition that in turn governs complex neuronal morphogenesis.
Topics: Animals; Cell Adhesion Molecules; Cell Communication; Drosophila Proteins; Gene Expression Regulation; Neurons; Protein Isoforms
PubMed: 22399408
DOI: 10.1007/978-1-4614-1704-0_17 -
Tsitologiia 2016Heat shock proteins are universal agents protecting all known organisms from environmental stresses. These proteins are classified into six families differing in their... (Review)
Review
Heat shock proteins are universal agents protecting all known organisms from environmental stresses. These proteins are classified into six families differing in their structure and function, yet having a common purpose of maintaining cellular proteins in operating condition. The small heat shock protein family has the most diversified set of effects on the organism’s vital activity with a great number of its members’ features studied thoroughly in a fruit fly Drosophila melanogaster, which is regarded as a convenient model object. In this review, we represent and discuss data on the role of Drosophila melanogaster Hsp67Bc protein, which was earlier identified as the closest functional ortholog of human HSPB8 small heat shock protein.
Topics: Animals; Drosophila Proteins; Drosophila melanogaster; Heat-Shock Proteins; Humans
PubMed: 30191693
DOI: No ID Found -
Methods in Molecular Biology (Clifton,... 2021In the early stages of Drosophila melanogaster (Drosophila) metamorphosis, a partial epithelial-mesenchymal transition (pEMT) takes place in the peripodial epithelium of...
In the early stages of Drosophila melanogaster (Drosophila) metamorphosis, a partial epithelial-mesenchymal transition (pEMT) takes place in the peripodial epithelium of wing imaginal discs. Blocking this pEMT results in adults with internalized wings and missing thoracic tissue. Using peripodial GAL4 drivers, GAL80 temporal control, and UAS RNAi transgenes, one can use these phenotypes to screen for genes involved in the pEMT. Dominant modifier tests can then be employed to identify genetic enhancers and suppressors. To analyze a gene's role in the pEMT, one can then visualize peripodial cells in vivo at the time of eversion within the pupal case using live markers, and by dissecting, fixing, and immunostaining the prepupae. Alternatively, one can analyze the pEMT ex vivo by dissecting out wing discs and culturing them in the presence of ecdysone to induce eversion. This can provide a clearer view of the cellular processes involved and permit drug treatments to be easily applied.
Topics: Animals; Drosophila Proteins; Drosophila melanogaster; Epithelial-Mesenchymal Transition; Genetic Techniques; Imaginal Discs; Phenotype; Tissue Culture Techniques; Wings, Animal
PubMed: 32939717
DOI: 10.1007/978-1-0716-0779-4_11 -
Nucleic Acids Research 2005NELF and DSIF act together to inhibit transcription elongation in vitro, and are implicated in causing promoter proximal pausing on the hsp70 gene in Drosophila. Here,...
NELF and DSIF act together to inhibit transcription elongation in vitro, and are implicated in causing promoter proximal pausing on the hsp70 gene in Drosophila. Here, further characterization of Drosophila NELF is provided. Drosophila NELF has four subunits similar to subunits of human NELF. The amino acid sequences of NELF-B and NELF-D are highly conserved throughout their lengths, while NELF-A and NELF-E contain nonconserved regions inserted between conserved N- and C-terminal regions. Immunodepletion of NELF or DSIF from a nuclear extract desensitizes transcription in vitro to DRB. Immunodepletion of NELF also impairs promoter proximal pausing on the hsp70 promoter in vitro without affecting initiation. Chromatin immunoprecipitation analyses detect NELF at the promoters of the hsp70 and beta1-tubulin genes where promoter proximal pausing has been previously detected. Heat shock induction of hsp70 results in a marked decrease in NELF at the hsp70 promoter. Immunofluorescence analysis of polytene chromosomes shows extensive colocalization of the NELF-B and NELF-D subunits at hundreds of interbands. Neither subunit appears to be recruited to puffs. These results provide a foundation for genetic and biochemical analysis of NELF in Drosophila.
Topics: Animals; Cell Line; Cell Nucleus; Chromatin; Chromosomes; Dichlororibofuranosylbenzimidazole; Drosophila; Drosophila Proteins; HSP70 Heat-Shock Proteins; Humans; Microscopy, Fluorescence; Nuclear Proteins; Nucleic Acid Synthesis Inhibitors; Promoter Regions, Genetic; Protein Subunits; Sequence Homology, Amino Acid; Transcription Factors; Transcription, Genetic; Tubulin
PubMed: 15741180
DOI: 10.1093/nar/gki274 -
Seminars in Cell & Developmental Biology Jun 2012It is well established that Notch signalling is activated in response to ligand binding through a series of proteolytic cleavages that release the Notch intracellular... (Review)
Review
It is well established that Notch signalling is activated in response to ligand binding through a series of proteolytic cleavages that release the Notch intracellular domain, allowing it to translocate to the nucleus to regulate downstream target gene expression. However there is still much to learn about the mechanisms that can bring about these proteolytic events in the numerous physiological contexts in which signal activation occurs. A number of studies have suggested that endocytosis of Notch contributes to the signal activation process, but the molecular details are unclear and controversial. There is conflicting data as to whether endocytosis of the receptor is essential for ligand-induced signalling or supplements it. Other studies have revealed that Notch can be activated in the endosomal pathway, independently of its ligands, through the activity of Deltex, a Ring-domain Ubiquitin ligase that binds to the Notch intracellular domain. However, it is unclear how the Deltex-activation mechanism relates to that of ligand-induced signalling, or to ectopic Notch signalling brought about by disruption of ESCRT complexes that affect multivesicular body formation. This review will address these issues and argue that the data are best reconciled by proposing distinct activation mechanisms in different cellular locations that contribute to the cellular pool of the soluble Notch intracellular domain. The resulting signalling network may provide developmental robustness to environmental and genetic variation.
Topics: Animals; Drosophila Proteins; Endocytosis; Gene Expression Regulation; Growth and Development; Humans; Membrane Proteins; Protein Transport; Proteolysis; Receptors, Notch; Signal Transduction
PubMed: 22285298
DOI: 10.1016/j.semcdb.2012.01.008 -
PloS One 2017Hybrid incompatibility between Drosophila melanogaster and D. simulans is caused by a lethal interaction of the proteins encoded by the Hmr and Lhr genes. In D....
Hybrid incompatibility between Drosophila melanogaster and D. simulans is caused by a lethal interaction of the proteins encoded by the Hmr and Lhr genes. In D. melanogaster the loss of HMR results in mitotic defects, an increase in transcription of transposable elements and a deregulation of heterochromatic genes. To better understand the molecular mechanisms that mediate HMR's function, we measured genome-wide localization of HMR in D. melanogaster tissue culture cells by chromatin immunoprecipitation. Interestingly, we find HMR localizing to genomic insulator sites that can be classified into two groups. One group belongs to gypsy insulators and another one borders HP1a bound regions at active genes. The transcription of the latter group genes is strongly affected in larvae and ovaries of Hmr mutant flies. Our data suggest a novel link between HMR and insulator proteins, a finding that implicates a potential role for genome organization in the formation of species.
Topics: Animals; Biodiversity; Drosophila; Drosophila Proteins; Genetic Speciation; Genome, Insect; Hybridization, Genetic
PubMed: 28207793
DOI: 10.1371/journal.pone.0171798 -
EMBO Reports Aug 2005The stereotyped outgrowth of tubular branches of the Drosophila tracheal system is orchestrated by the local and highly dynamic expression profile of branchless (bnl),...
The stereotyped outgrowth of tubular branches of the Drosophila tracheal system is orchestrated by the local and highly dynamic expression profile of branchless (bnl), which encodes a secreted fibroblast growth factor (FGF)-like molecule. Despite the importance of the spatial and temporal bnl regulation, little is known about the upstream mechanisms that establish its complex expression pattern. Here, we show that the Extradenticle and Homothorax selector proteins control bnl transcription in a single cell per segment, the mesodermal bridge-cell. In addition, we observed that a key determinant of bridge-cell specification, the transcription factor Hunchback, is also required for bnl expression. Therefore, we propose that one of the functions of the bridge-cell is to synthesize and secrete the chemoattractant Bnl. These findings provide a hitherto unknown and interesting link between combinatorial inputs of transcription factors, cell-specific ligand expression and organ morphogenesis.
Topics: Alleles; Animals; DNA-Binding Proteins; Drosophila Proteins; Drosophila melanogaster; Fibroblast Growth Factors; Gene Expression Regulation; Gene Expression Regulation, Developmental; Green Fluorescent Proteins; Homeodomain Proteins; Homozygote; In Situ Hybridization; Ligands; Mesoderm; Mutation; Recombinant Proteins; Transcription Factors; Transcription, Genetic; Transgenes
PubMed: 16007069
DOI: 10.1038/sj.embor.7400462 -
The European Journal of Neuroscience Aug 2014In Drosophila, serotonin (5-HT) regulates aggression, mating behaviour and sleep/wake behaviour through different receptors. Currently, how these various receptors are...
In Drosophila, serotonin (5-HT) regulates aggression, mating behaviour and sleep/wake behaviour through different receptors. Currently, how these various receptors are themselves regulated is still not completely understood. The KCTD12-family of proteins, which have been shown to modify G-protein-coupled receptor (GPCR) signalling in mammals, are one possibility of auxiliary proteins modulating 5-HT receptor signalling. The KCTD12-family was found to be remarkably conserved and present in species from C. elegans to humans. The Drosophila KCTD12 homologue Kctd12-like (Ktl) was highly expressed in both the larval and adult CNS. By performing behavioural assays in male Drosophila, we now reveal that Ktl is required for proper male aggression and mating behaviour. Previously, it was shown that Ktl is in a complex with the Drosophila 5-HT receptor 5-HT7, and we observed that both Ktl and the 5-HT1A receptor are required in insulin-producing cells (IPCs) for proper adult male behaviour, as well as for hyperaggressive activity induced by the mammalian 5-HT1A receptor agonist 8-hydroxy-2-dipropylaminotetralin-hydrobromide. Finally, we show that Ktl expression in the IPCs is necessary to regulate locomotion and normal sleep/wake patterns in Drosophila, but not the 5-HT1A receptor. Similar to what was observed with mammalian KCTD12-family members that interact physically with a GPCR receptor to regulate desensitization, in Drosophila Ktl may function in GPCR 5-HT receptor pathways to regulate their signalling, which is required for proper adult male behaviour.
Topics: Aggression; Animals; Brain; Drosophila Proteins; Drosophila melanogaster; Female; Gene Expression; Male; Motor Activity; Receptors, Serotonin, 5-HT1; Sequence Analysis, Protein; Sexual Behavior, Animal
PubMed: 24830553
DOI: 10.1111/ejn.12619