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ELife May 2024is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid...
is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid droplets (LD), to sperm development is largely unknown. Emerging evidence suggests LD are present in the testis and that loss of neutral lipid- and LD-associated genes causes subfertility; however, key regulators of testis neutral lipids and LD remain unclear. Here, we show LD are present in early-stage somatic and germline cells within the testis. We identified a role for triglyceride lipase () in regulating testis LD, and found that whole-body loss of leads to defects in sperm development. Importantly, these represent cell-autonomous roles for in regulating testis LD and spermatogenesis. Because lipidomic analysis of mutants revealed excess triglyceride accumulation, and spermatogenic defects in mutants were rescued by genetically blocking triglyceride synthesis, our data suggest that -mediated regulation of triglyceride influences sperm development. This identifies triglyceride as an important neutral lipid that contributes to sperm development, and reveals a key role for in regulating testis triglyceride levels during spermatogenesis.
Topics: Spermatogenesis; Animals; Male; Triglycerides; Drosophila Proteins; Testis; Drosophila melanogaster; Lipase; Lipid Droplets; Spermatozoa
PubMed: 38805376
DOI: 10.7554/eLife.87523 -
Frontiers in Immunology 2024Since infections with antibiotic-resistant bacteria cause increasing problems worldwide, the identification of alternative therapies is of great importance....
Since infections with antibiotic-resistant bacteria cause increasing problems worldwide, the identification of alternative therapies is of great importance. Plant-derived bioactives, including allyl-isothiocyanate (AITC), have received attention for their antimicrobial properties. The present study therefore investigates the impact of AITC on survival and antimicrobial peptide (AMP) levels in challenged with the fly pathogenic bacteria subsp. and . AITC, a sulfur-containing compound derived from glucosinolates, exhibits antimicrobial properties and has been suggested to modulate AMP expression. By using , we demonstrate that AITC treatment resulted in a concentration-dependent decrease of survival rates among female flies, particularly in the presence of the Gram-negative bacterium subsp. , whereas AITC did not affect survival in male flies. Despite the ability of isothiocyanates to induce AMP expression in cell culture, we did not detect significant changes in AMP mRNA levels in infected flies exposed to AITC. Our findings suggest sex-specific differences in response to AITC treatment and bacterial infections, underlining the complexity of host-pathogen interactions and potential limitations of AITC as a preventive or therapeutic compound at least in models of bacterial infections.
Topics: Animals; Isothiocyanates; Drosophila melanogaster; Female; Male; Antimicrobial Peptides; Pectobacterium carotovorum; Drosophila Proteins
PubMed: 38803500
DOI: 10.3389/fimmu.2024.1404086 -
Frontiers in Molecular Neuroscience 2024Aging is defined as a progressive decline of cognitive and physiological functions over lifetime. Since the definition of the nine hallmarks of aging in 2013 by... (Review)
Review
Aging is defined as a progressive decline of cognitive and physiological functions over lifetime. Since the definition of the nine hallmarks of aging in 2013 by López-Otin, numerous studies have attempted to identify the main regulators and contributors in the aging process. One interesting group of proteins whose participation has been implicated in several aging hallmarks are the nuclear DBF2-related (NDR) family of serine-threonine AGC kinases. They are one of the core components of the Hippo signaling pathway and include NDR1, NDR2, LATS1 and LATS2 in mammals, along with its highly conserved metazoan orthologs; Trc in , SAX-1 in , CBK1, DBF20 in and orb6 in . These kinases have been independently linked to the regulation of widely diverse cellular processes disrupted during aging such as the cell cycle progression, transcription, intercellular communication, nutrient homeostasis, autophagy, apoptosis, and stem cell differentiation. However, a comprehensive overview of the state-of-the-art knowledge regarding the post-translational modifications of and by NDR kinases in aging has not been conducted. In this review, we summarize the current understanding of the NDR family of kinases, focusing on their relevance to various aging hallmarks, and emphasize the growing body of evidence that suggests NDR kinases are essential regulators of aging across species.
PubMed: 38803357
DOI: 10.3389/fnmol.2024.1371086 -
Narra J Apr 2024It is widely acknowledged that smoking exacerbates the severity of infectious diseases. A presumed mechanism involves the damage inflicted by tobacco smoke on the organs...
It is widely acknowledged that smoking exacerbates the severity of infectious diseases. A presumed mechanism involves the damage inflicted by tobacco smoke on the organs of host organisms. In this study, an alternative hypothesis was explored: smoking enhances the virulence of bacteria. This possibility was investigated using as the model bacteria and as the host organism. Our inquiry focused on the potential gene expression changes in subsequent to exposure to tobacco smoke extracts. Analysis of the transcription promoter activity of genes encoding proteins within the two-component system, a regulatory machinery governing gene expression, revealed the suppression of thirteen out of 23 promoters in response to tobacco smoke extracts. Subsequently, was infected with exposed to tobacco smoke extracts or left untreated. Interestingly, there were no significant differences observed in the survival periods of following infection with , whether treated or untreated with tobacco smoke extracts. Contrary to the initial hypothesis, the findings suggest that while tobacco smoke extracts alter gene expression in , these changes do not appear to impact bacterial virulence. Although this study has illuminated the influence of tobacco smoke extracts on the gene expression of , further analyses are necessary to elucidate the implications of these changes. Nevertheless, the results imply that smoking affects not only host organisms but may also exert influence on invading bacteria.
Topics: Escherichia coli; Animals; Virulence; Nicotiana; Drosophila; Gene Expression Regulation, Bacterial; Smoke; Virulence Factors
PubMed: 38798851
DOI: 10.52225/narra.v4i1.754 -
BioRxiv : the Preprint Server For... May 2024RNA editing is a post-transcriptional source of protein diversity and occurs across the animal kingdom. Given the complete profile of mRNA targets and their editing rate...
RNA editing is a post-transcriptional source of protein diversity and occurs across the animal kingdom. Given the complete profile of mRNA targets and their editing rate in individual cells is unclear, we analyzed single cell RNA transcriptomes from larval tonic and phasic glutamatergic motoneuron subtypes to determine the most highly edited targets and identify cell-type specific editing. From ∼15,000 genes encoded in the genome, 316 high confidence A-to-I canonical RNA edit sites were identified, with 102 causing missense amino acid changes in proteins regulating membrane excitability, synaptic transmission, and cellular function. Some sites showed 100% editing in single neurons as observed with mRNAs encoding mammalian AMPA receptors. However, most sites were edited at lower levels and generated variable expression of edited and unedited mRNAs within individual neurons. Together, these data provide insights into how the RNA editing landscape alters protein function to modulate the properties of two well-characterized neuronal populations in .
PubMed: 38798345
DOI: 10.1101/2024.05.17.594696 -
Nature Communications May 2024As daughter centrioles assemble during G2, they recruit conserved Ana3/RTTN followed by its partner Rcd4/PPP1R35. Together, this contributes to the subsequent...
As daughter centrioles assemble during G2, they recruit conserved Ana3/RTTN followed by its partner Rcd4/PPP1R35. Together, this contributes to the subsequent recruitment of Ana1/CEP295, required for the centriole's conversion to a centrosome. Here, we show that Rcd4/PPP1R35 is also required to maintain 9-fold centriole symmetry in the Drosophila male germline; its absence causes microtubule triplets to disperse into a reduced number of doublet or singlet microtubules. rcd4-null mutant spermatocytes display skinny centrioles that elongate normally and localize centriolar components correctly. Mutant spermatocytes also have centrioles of normal girth that splay at their proximal ends when induced to elongate by Ana1 overexpression. Skinny and splayed spermatid centrioles can still recruit a proximal centriole-like (PCL) structure marking a capability to initiate features of centriole duplication in developing sperm. Thus, stable 9-fold symmetry of microtubule triplets is not essential for centriole growth, correct longitudinal association of centriole components, and aspects of centriole duplication.
Topics: Centrioles; Animals; Male; Drosophila Proteins; Spermatocytes; Microtubules; Drosophila melanogaster; Spermatids; Cell Cycle Proteins; Microtubule-Associated Proteins; Mutation; Drosophila
PubMed: 38796459
DOI: 10.1038/s41467-024-48831-y -
Cell Reports Jun 2024The decline of motor ability is a hallmark feature of aging and is accompanied by degeneration of motor synaptic terminals. Consistent with this, Drosophila motor...
The decline of motor ability is a hallmark feature of aging and is accompanied by degeneration of motor synaptic terminals. Consistent with this, Drosophila motor synapses undergo characteristic age-dependent structural fragmentation co-incident with diminishing motor ability. Here, we show that motor synapse levels of Trio, an evolutionarily conserved guanine nucleotide exchange factor (GEF), decline with age. We demonstrate that increasing Trio expression in adult Drosophila can abrogate age-dependent synaptic structural fragmentation, postpone the decline of motor ability, and maintain the capacity of motor synapses to sustain high-intensity neurotransmitter release. This preservative activity is conserved in transgenic human Trio, requires Trio Rac GEF function, and can also ameliorate synapse degeneration induced by depletion of miniature neurotransmission. Our results support a paradigm where the structural dissolution of motor synapses precedes and promotes motor behavioral diminishment and where intervening in this process can postpone the decline of motor function during aging.
Topics: Animals; Aging; Synapses; Humans; Guanine Nucleotide Exchange Factors; Drosophila melanogaster; Drosophila Proteins; Motor Neurons; Motor Activity; Synaptic Transmission; Protein Serine-Threonine Kinases
PubMed: 38795343
DOI: 10.1016/j.celrep.2024.114256 -
Cell Reports Jun 2024The suppressive effect of insulin on food intake has been documented for decades. However, whether insulin signals can encode a certain type of nutrients to regulate...
The suppressive effect of insulin on food intake has been documented for decades. However, whether insulin signals can encode a certain type of nutrients to regulate nutrient-specific feeding behavior remains elusive. Here, we show that in female Drosophila, a pair of dopaminergic neurons, tritocerebrum 1-dopaminergic neurons (T1-DANs), are directly activated by a protein-intake-induced insulin signal from insulin-producing cells (IPCs). Intriguingly, opto-activating IPCs elicits feeding inhibition for both protein and sugar, while silencing T1-DANs blocks this inhibition only for protein food. Elevating insulin signaling in T1-DANs or opto-activating these neurons is sufficient to mimic protein satiety. Furthermore, this signal is conveyed to local neurons of the protocerebral bridge (PB-LNs) and specifically suppresses protein intake. Therefore, our findings reveal that a brain-derived insulin signal encodes protein satiety and suppresses feeding behavior in a nutrient-specific manner, shedding light on the functional specificity of brain insulin signals in regulating behaviors.
Topics: Animals; Insulin; Brain; Signal Transduction; Female; Feeding Behavior; Drosophila Proteins; Dopaminergic Neurons; Drosophila melanogaster; Satiety Response; Nutrients
PubMed: 38795342
DOI: 10.1016/j.celrep.2024.114282 -
Plants (Basel, Switzerland) May 2024The γ-aminobutyric acid (GABA) receptors play pivotal roles in the transmission of neuronal information in the nervous system of insects, which has led these proteins...
The γ-aminobutyric acid (GABA) receptors play pivotal roles in the transmission of neuronal information in the nervous system of insects, which has led these proteins to be targeted by synthetic and natural products. Here, we assessed the insecticidal potential of the essential oil of (Gardner) Sch. Bip., a neotropical Asteraceae plant used in traditional medicine, for controlling (Matsumura) adults by feeding exposure. By using in silico approaches, we disentangle the contribution of GABA receptors and other potential neuronal targets (e.g., acetylcholinesterase, glutathione-S-transferases) in insects that may explain the essential oil differential activities against and two essential pollinator bees ( Linnaeus and Friese). Neral (26.7%) and geranial (33.9%) were the main essential oil components which killed with an estimated median lethal concentration (LC) of 2.25 µL/mL. Both pollinator forager bee species, which would likely contact this compound in the field, were more tolerant to the essential oil and did not have their diet consumptions affected by the essential oil. Based on the molecular predictions for the three potential targets and the essential oil main components, a higher affinity of interaction with the GABA receptors of (geranial -6.2 kcal/mol; neral -5.8 kcal/mol) in relation to (geranial -5.2 kcal/mol; neral -4.9 kcal/mol) would contribute to explaining the difference in toxicities observed in the bioassays. Collectively, our findings indicated the involvement of GABA receptors in the potential of essential oil as an alternative tool for controlling .
PubMed: 38794461
DOI: 10.3390/plants13101392 -
Molecules (Basel, Switzerland) May 2024A previous study reported that the ethanolic extract of the edible fern, (Retz.) Sw. (DE), obtained from a non-optimized extraction condition exhibited anti-Alzheimer's...
A previous study reported that the ethanolic extract of the edible fern, (Retz.) Sw. (DE), obtained from a non-optimized extraction condition exhibited anti-Alzheimer's disease (AD) properties through the inhibition of a rate-limiting enzyme in amyloid peptide formation, β-secretase-1 (BACE-1). Nevertheless, a non-optimized or suboptimal extraction may lead to several issues, such as a reduction in extraction efficiency and increased time and plant materials. In this study, extraction of the DE was optimized to obtain appropriate BACE-1 inhibition using a Box-Behnken design (BBD) and response surface methodology (RSM). Data revealed that the optimal extraction condition was 70% (/) aqueous ethanol, 50 min extraction time, 30 °C extraction temperature, and 1:30 g/mL solid/liquid ratio, giving BACE-1 inhibition at 56.33%. In addition, the extract also exhibited significant antioxidant activities compared to the non-optimized extraction. Metabolomic phytochemical profiles and targeted phytochemical analyses showed that kaempferol, quercetin, and their derivatives as well as rosmarinic acid were abundant in the extract. The optimized DE extract also acted synergistically with donepezil, an AD drug suppressing BACE-1 activities. Data received from -expressing human amyloid precursor proteins (APPs) and BACE-1, representing the amyloid hypothesis, showed that the optimized DE extract penetrated the fly brains, suppressed BACE-1 activities, and improved locomotor functions. The extract quenched the expression of glutathione S transferase D1 (GSTD1), inositol-requiring enzyme (IRE-1), and molecular chaperone-binding immunoglobulin (Bip), while donepezil suppressed these genes and other genes involved in antioxidant and endoplasmic reticulum (ER) stress response, including superoxide dismutase type 1 (SOD1), activating transcription factor 6 (ATF-6), and protein kinase R-like endoplasmic reticulum kinase (PERK). To sum up, the optimized extraction condition reduced extraction time while resulting in higher phytochemicals, antioxidants, and BACE-1 inhibitors.
Topics: Antioxidants; Alzheimer Disease; Plant Extracts; Phytochemicals; Amyloid Precursor Protein Secretases; Animals; Ferns; Humans; Aspartic Acid Endopeptidases
PubMed: 38792065
DOI: 10.3390/molecules29102204