Juan Rafael Riesgo-Escovar

This study characterizes the requirements of the kayak ( kay ) gene in Drosophila melanogaster adult eye biology by examining mutant phenotypes in photoreceptor development, external eye morphology, corneal and bristle ultrastructure, and visually guided behaviors, such as phototaxis, in kay strong loss-of-function homozygous mutant clones. Despite previous studies on kay , there is a dearth of phenotypic characterization of the morphological and behavioral consequences of kay loss-of-function alleles in the adult eye. We find that kay is expressed in developing ommatidia in eye discs. The kay mutant ommatidia are misaligned, lack photoreceptors, have malformed corneal surfaces, and have misshaped, misplaced, and fewer mechanosensory bristles. Corneal nipples, while present in mutant corneas on the corneal surface, are disorganized and malformed. With an average of 30% of the eye territory mutant, flies have a significantly lower response in a behavioral phototaxis assay. Altogether, kay function is required for multiple cell types in the adult retina, and this stands in stark contrast with other jun kinase genes, like the fly homologs of jun kinase and jun , genes not required for adult eye morphogenesis. This is consistent with Kayak functions that are independent of heterodimerizing with Jun proteins or requiring activation of the jun kinase pathway.

Background/Objectives: Obesity-related insulin resistance leads to the development of type 2 diabetes mellitus (T2DM); however, the pathophysiology of these metabolic alterations remains incompletely understood. This study aimed to characterize the lipidomic alterations during obesity–insulin resistance–T2DM progression in a high-sugar diet (HSD) model. Methods: Fruit flies were fed either a standard diet (SD) or an HSD and monitored across a 14-day period. Metabolic phenotyping and lipidomic profiling were conducted during the experiment. Results: After two days of HSD, fruit flies exhibited an obesity phenotype (50% increase in triglyceride content) and insulin resistance (hyperglycemia and insulin overexpression), progressing to an early T2DM-like state (increased triglycerides, hyperglycemia, and normal insulin expression) from days 4 to 6, and finally to a late T2DM-like phenotype (increased triglycerides, hyperglycemia, and insulin down-regulation) from days 8 to 14. Multivariate analyses indicated an altered lipidome profile in HSD-fed fruit flies from day 2 until the end of the experiment. Fatty acids and phosphatidylethanolamines (PEs) containing 16:0, 16:1, and 18:1 acyl chains were significantly altered during the development of obesity-related insulin resistance and early T2DM-like state (days 2 to 6); whereas palmitic acid and oleic acid-LysoPE alterations were associated with the onset and progression of obesity-related T2DM-like state (days 4 to 14). Conclusions: The progression from obesity-related insulin resistance to a T2DM-like state in an HSD-fed D. melanogaster model is accompanied by distinct lipidomic signatures involving 16- and 18-carbon fatty acid derivatives. These findings provide insight into potential biomarkers and mechanistic pathways in the early pathogenesis of T2DM.

Editorial: Emerging frontiers in developmental biology in Latin America

The metabolic effects of chronic consumption of food laced with different doses of moringa leaf powder (MLP) were assessed using a heteroallelic mutant of the sole insulin receptor gene of Drosophila melanogaster (InR), and the yellow,white (y,w) control stock. The MLP composition was partially determined. Both strains were raised in a standard diet (SD) or in a SD supplemented with different MLP doses (0.5, 1.5, 2.5, 4.0, and 5.5%) until 4–5 days of emergence. Afterward, the total carbohydrate, lipid, glucose, and triacylglyceride levels were measured in the flies. Additionally, survival and weight changes were reported. For metabolic tests, female and male virgin flies were evaluated separately. Low MLP supplementation improved carbohydrate and glucose levels in the y,w strain. Additionally, the InR-mutant strain reported lower lipid content when subjected to the same regimes. Survival improved in both strains with low MLP doses, while chronic consumption of high MLP doses resulted in triacylglycerides increase, weight gain, and survival reduction. Low doses of MLP supplementation improves some metabolic parameters that affect flies’ survival, especially in the y,w strain. Furthermore, the same low doses of MLP treatments also resulted in metabolic improvements in the InR-mutant flies; however, MLP consumption levels should be carefully assessed. Supplemental data for this article is available online at

LncRNAs, genes transcribed but not translated, longer than 200 nucleotides, are classified as a separate class of nonprotein coding genes. Since their discovery, largely from RNAseq data, a number of pioneer studies have begun to unravel its myriad functions, centered on gene expression regulation, suggesting developmental and evolutionary conservation. Since they do not code for proteins and have no open reading frames, their functional constraints likely differ from that of protein coding genes, or of genes where the majority of the nucleotide sequence is required for function, like tRNAs. This has complicated assessment of both developmental and evolutionary conservation, and the identification of homologs in different species. Here we argue that other characteristics: general synteny and particular chromosomal placement regardless of sequence, sequence micro‐motifs, and secondary structure allow for “homologs” to be identified and compared, confirming developmental and evolutionary conservation of lncRNAs. We conclude exemplifying a case in point: that of the evolutionarily conserved lncRNA acal, characterized and required for embryogenesis in Drosophila.