Cells in metabolically active tissues with high biosynthetic and secretory demands often use robust stress-responsive mechanisms to maintain homeostasis. Coordinating such stress response mechanisms requires intercellular communication and coordination. Such modalities of intercellular communication have been relatively understudied in the context of stress tolerance. Here, we use the Drosophila melanogaster third instar fat body to demonstrate that adipocytes communicate with each other through intercellular bridges called ring canals to buffer endoplasmic reticulum (ER) stress. The fat body supports the exponential growth from embryo to late larval stage over a short period of time through its energy storage and secretory functions, enduring a high basal level of stress in the process. We discovered that individual cells in the fat body are paired to one neighboring cell through ring canals. We further demonstrate that ring canals mediate rapid and highly specific intercellular cargo and organellar trafficking, and allow the transport of cytoplasmic, ER-bound, and Golgi vesicular proteins. Disrupting fat body ring canals resulted in higher levels of stress response markers, aberrant cell size, and increased cell sensitivity and lethality in response to various exogenous stressors. We also find that animals with disrupted fat body ring canals display an overall delay in larval development, likely due to reduced secretion of larval serum proteins from the fat body. In sum, our work reveals a novel feature of intercellular communication in adipose tissue that serves to buffer stress across cells, which is required for both homeostatic secretory function and maintaining tissue viability under exogenous stress.

Maternal Tauroursodeoxycholic Acid Supplementation under Isocaloric High-Fat Diet Alleviates Oxidative Stress and Extends Lifespan through a whd-Dependent Mechanism in Drosophila Offspring.

Sulfonylurea receptor integrates calcium homeostasis and insulin-like peptide signaling to regulate energy metabolism and larval development in Hyphantria cunea.

Larval and pupal development in Hermetia illucens: developmental checkpoints and starvation-induced dormancy.

The adipokinetic hormones of stored product pest insects: can this help to combat these insects?

A major factor underlies biliverdin-mediated blue pigmentation in the Chinese oak silkworm Antheraea pernyi.

Plant sap-feeding insects (Hemiptera: Auchenorrhyncha) with rich species diversity generally harbor obligate endosymbionts within their specialized symbiotic organs (i.e., bacteriomes) to supplement them with essential amino acids (EAAs) and B vitamins that are unavailable in their nutritionally unbalanced diet, representing a typical model of insect-microbe symbioses. However, the processes of symbiont translocation and morphogenesis of bacteriomes during embryonic development remain unclear in Auchenorrhyncha. Here, we assessed symbiont replacement events in representative species across the five auchenorrhynchan superfamilies, and investigated the symbiont communities of eggs and morphogenesis of symbiotic organs during embryonic development as well as nutritional roles that related obligate symbionts play using multiple approaches. We revealed differences in the provision of EAAs by the same obligate symbiont across various auchenorrhynchan lineages, and demonstrated that the morphogenesis of symbiotic organs is closely associated with the symbiont community: (i) hosts acquiring only obligate symbiotic bacteria form bacteriomes to harbor them; (ii) hosts having only a yeast-like fungal symbiont (YLS) form fat bodies to harbor the YLS cells, but no bacteriomes evolved; and (iii) hosts harboring both obligate symbiotic bacteria and YLS form bacteriomes to harbor bacteria, and YLS gradually migrate to the fat bodies with the development of the host insects, although they initially co-colonized the bacteriomes. The results indicate that only the obligate bacterial symbiont(s) initiate the morphogenesis and formation of the bacteriomes. It highlights adaptive mechanisms underlying the origin and evolution of symbiotic organs in plant sap-feeding insects and provides new insights into their co-evolution with microbial partners.

The evolutionary and developmental origins of affective states (emotions, feelings) remain unresolved. We propose and empirically test the Hepato‑Affective Primacy (HAP) Theory — Strong Version: affective states are impossible in any bilaterian animal that lacks an organ performing two critical functions — (1) secretion of steroidal regulatory molecules (bile acids, ecdysteroids, or functional analogs) acting via nuclear receptors, and (2) a barrier‑detoxification function for circulating fluid (blood/hemolymph). A systematic meta‑analysis of 56 bilaterian taxa (12 phyla) reveals perfect correlation: all 32 taxa with well‑documented affective behavior possess a functional hepatic organ meeting our a priori criteria; all 24 taxa without such an organ lack evidence of affect (exhibiting only simple reflexes or non‑affective learning). Key cases that could falsify the theory — cephalopods (hepatopancreas), insects (fat body + pericardial cells secreting ecdysteroids), and annelids (no organ, no affect) — each support the hypothesis. The major limitation is unfalsifiability in vertebrates due to embryonic lethality after hepatectomy. We propose surrogate experimental designs (conditional hepatocyte ablation in zebrafish after neurulation) to address this. We conclude that HAP Strong Version is empirically supported across all accessible bilaterian taxa and provides a unifying evolutionary principle: a hepatic organ is the phylogenetic and ontogenetic precondition for affective states.

Dual-energy X-ray absorptiometry (DXA) is widely used to assess body composition, but differences in device calibration, software, and scan modes across manufacturers hinder data harmonization in multi-site studies. To develop and validate regression models that convert body composition measurements among three DXA systems, GE iDXA, Hologic Horizon A, and Hologic Discovery A, and deploy these models in an accessible web-based tool. A cohort of 101 adults completed same-day whole-body scans on all three machines. Fat mass (FM), lean soft tissue (LST), fat-free mass (FFM), bone mineral content (BMC), and % fat body fat were extracted. Pearson correlations quantified measurement agreement. For each device pair, we developed unadjusted, age-adjusted, and age and sex regression models and evaluated generalizability using leave-one-out cross-validation (Q²). Bland-Altman analyses assessed bias and limits of agreement. A user-friendly web-based application was developed deploy the conversions. Correlations between DXA machines were high across all body composition measures (% body fat: r = 0.96-0.98; FM: r = 0.98-0.99; LST: r = 0.97-0.99). Adjusted R² values exceeded 0.95 for nearly all regression models, with lower performance observed for FFM conversions involving the Horizon device (adjusted R² = 0.84-0.86). Bland-Altman analysis of % body fat conversions revealed mean bias ranging from 1.02 percentage points for iDXA-to-Discovery to 4.24 percentage points for Discovery-to-Horizon. The Discovery-to-Horizon conversion exhibited a 95% confidence interval entirely above zero , indicating systematic overestimation of Horizon % body fat. In contrast, the iDXA-to-Discovery conversion showed narrower limits of agreement with no evident proportional error. Several conversions demonstrated proportional bias, including Horizon-to-Discovery and Discovery-to-iDXA % body fat predictions, characterized by overestimation at lower adiposity and underestimation at higher adiposity levels. Same-day, same-subject measurements across three DXA systems enabled development of machine-to-machine conversion equations with high predictive accuracy for most body composition variables and greater variability for FFM. The accompanying web-based tool provides a practical resource for applying these equations at scale and reducing inter-device measurement differences in multi-site datasets.

Sterol Carrier Protein X (SCP-x) is an evolutionarily conserved lipid transport protein that plays important roles in sterol metabolism. In insects, cholesterol is an essential component of cellular membranes and the precursor of ecdysteroids, yet insects cannot synthesize cholesterol de novo and must obtain it from dietary sources. However, the functional role of SCP-x in cholesterol absorption and transport in insects remains poorly understood. In this study, the SCP-x gene from the migratory locust Locusta migratoria was identified and characterized using transcriptomic data from the midgut and fat body. The full-length LmSCP-x encodes a 404-amino-acid protein containing both the 3-oxoacyl-CoA thiolase domain and the sterol carrier protein-2 domain. Expression analysis revealed that LmSCP-x is predominantly expressed in the midgut and fat body, and subcellular localization experiments showed that the protein is mainly distributed in the cytoplasm. RNA interference-mediated knockdown of LmSCP-x significantly reduced cholesterol levels in the fat body and delayed nymphal development. Structural prediction using AlphaFold 3 further revealed a conserved three-dimensional structure of the SCP-2 domain, and molecular docking identified key amino acid residues involved in cholesterol binding, which were subsequently validated by bio-layer interferometry assays. Together, these results demonstrate that LmSCP-x plays a crucial role in cholesterol transport in L. migratoria and provide new insights into sterol metabolism in insects, offering potential targets for the development of novel pest management strategies.

ABSTRACT Sulphur-containing amino acids (SAAs), including methionine and cysteine, play crucial roles in antioxidant defence, anti-ageing, cytoprotection, and anti-inflammatory responses. Previous studies have shown that SAAs promote peroxisome elevation and fat loss by inducing the expression of the peroxisome-related gene CG33474 in the Drosophila fat body. However, the underlying regulatory mechanism remains unclear. In this study, we demonstrated that the transsulphuration pathway contributes to CG33474 induction, as supplementation with specific downstream metabolites of this pathway recapitulates this effect. Moreover, we found that SAAs upregulate not only CG33474 but also several neighbouring genes – including CG11825, Prx2540-1, Prx2540-2, and CG12896 – suggesting coordinated regulation within this genomic locus. Through fluorescence reporter assays, we discovered that a ~1 kb genomic region upstream of CG33474 harbours the cis-regulatory element mediating SAA responsiveness and that this responsiveness is fat body-specific. Finally, our data suggest that induction of CG33474 may play a role in resistance to different stresses and in regulating ageing as fat body-specific overexpression of CG33474 significantly extends lifespan in Drosophila. Together, our findings reveal that SAAs modulate the expression of CG33474 and its adjacent genes through the transsulphuration pathway, providing an additional mechanistic basis for the antioxidant effects of SAAs.

Species and sex-specific differences in organ size are fundamental features of animal biology, yet the mechanisms that drive these differences remain debated. Adult female Drosophila are larger than males. While most organs are present across both sexes, the underlying mechanisms driving sex-specific organ and body size scaling of Drosophila remain unclear. Using single-nucleus transcriptomes from the Fly Cell Atlas, combined with experimental validation, we show that different Drosophila organs scale through distinct strategies, including cell size, cell number, or a combination of both, in an allometric rather than uniform manner. Larger female flight muscles develop from more myoblasts than in males, while cardiomyocyte numbers are the same despite forming a larger heart in females. Female fat body cells are larger and express more ribosomal protein-coding mRNAs, supporting increased cell size per nucleus. In contrast, males have a greater number of fat body cells. Together, this sex-specific allometry in cell size and nuclei number define the cellular basis for differences in body and organ size between sexes in Drosophila. By uncovering how a developmental system produces sex-specific proportions through distinct cellular strategies, our work offers a framework for dissecting sex differences in other species and systems.

The transcription factor CncC/Maf modulates imidacloprid susceptibility by regulating UGT392C1 in Locusta migratoria.

Pipiserpin orchestrates mosquito reproduction through dual control of vitellogenin integrity and 20-hydroxyecdysone-directed vitellogenesis.

Ganglioneuroma in a Meller's chameleon (Triocerosmelleri).

A Meta-Analysis of Body Composition Changes Associated With Long-term Use of Sodium-Glucose Cotransporter 2 Inhibitors.

Bioimaging and distribution of unmodified and polyethylene glycol-modified up-converting SrF2:Yb3+,Er3+ nanoparticles in Tenebrio molitor larvae and their impact on lifespan, moulting, and metabolism.

Substituting fresh mulberry leaves with artificial (compound) diets is a growing trend in industrialized sericulture. However, breeder silkworms (Bombyx mori, Lepidoptera: Bombycidae) reared on artificial diets (ADs) throughout their larval stage exhibit severely impaired reproductive fitness, which is a major bottleneck and the mechanism responsible remains unclear. In this study, we demonstrated that rearing on AD inhibited 20-hydroxyecdysone (20E) signaling during the pupal stage, thereby interfering with the synthesis and transport of vitellogenin and 30Kc19 in the fat body. This perturbation caused the abnormal accumulation of 30Kc19 and egg-specific protein in the ovary, as well as severe glycogen deficiency, which ultimately suppressed oogenesis, reduced the egg quantity and quality, and triggered transgenerational declines in offspring viability and reproductive performance. Exogenous 20E supplementation effectively restored the female reproductive capacity. Thus, we elucidated the mechanism responsible for the reproductive decline of silkworms reared on AD, providing a theoretical foundation for intervention strategies.

Mitigation effects of short-chain fatty acids on microplastic accumulation in plastic-degrading Zophobas morio larvae and mechanistic insights.

The hemolymph of crustaceans (decapods, isopods, amphipods, copepods, branchiopods, cirripedes) and chelicerates (ticks, mites, spiders, scorpions, horseshoe crabs) contain female-specific and sex-independent lipoproteins in the high-density lipoprotein (HDL, density: 1.063-1.21 g/ml) and very high-density lipoprotein (VHDL, density>1.21 g/ml) classes. The first part of this review includes the history of the important developments in the study of hemolymph lipoproteins, synthesis by different tissues, important functions and synthesis/utilization by developing embryos. The sex-independent and female-specific lipoprotein have very different functions. The sex-independent lipoprotein functions include clotting, pattern recognition and transport of lipids, hormones, vitamins, heme and pheromones. Female-specific lipoproteins primarily serve as a source of energy and nutrition for developing embryos. Female-specific lipoproteins are assembled in the ovary, hepatopancreas, fat body or mid-gut and after the peptide is cleaved into subunits the lipoproteins are secreted into the hemolymph with subsequent uptake into the developing oocytes by receptor-mediated endocytosis. The second part of the review covers the past two decades of work which focused on the genes that encode the lipoproteins and determination of their amino acid sequences. Most crustacean and chelicerate lipoproteins are in the apolipoprotein B-like (apoB-like) or the vitellogenin-like (Vg-like) families of the superfamily of large lipid transfer proteins involved in the assembly, secretion and metabolism of lipoproteins. Decapod female-specific lipoproteins, vitellogenin/apocrustacein (Vg/apoCr), are in the apoB-like family while the female-specific lipoproteins in other crustacean groups and chelicerates are in the Vg-like family. Each family is characterized by certain major structural domains which are responsible for lipid binding, carbohydrate attachment and receptor binding.