Lsp2 links mTORC1 to TOP mRNA translation and lifespan in Drosophila
In Drosophila, the previously known storage protein Lsp2 also acts as an adipose effector and feedback activator of mTORC1; removing Lsp2 extended lifespan and selectively reduced TOP mRNA translation in a 4E-BP-dependent way, a mechanism the authors describe as distinct from rapamycin's effects. [1]
Automatic summary · not editorially reviewed
The key findings
Lsp2, previously known as a storage protein, is also described as an adipose effector and feedback activator of mTORC1 in Drosophila. [1]
Genetic ablation of Lsp2 robustly extended lifespan without impairing key life history traits such as reproduction. [1]
Loss of Lsp2 selectively reduced global TOP mRNA translation in a 4E-BP-dependent manner, a mechanism the authors describe as distinct from rapamycin's effects. [1]
The source at a glance
- Study type / format
- Preclinical study in Drosophila (abstract only)
- Population / context
- Drosophila (fruit flies) in the described experiments
- Summary based on
- Study abstract
- Original publication
- September 23, 2026
Lsp2 as nutrient-induced mTORC1 feedback activator
The abstract describes mTORC1 as sensing nutrient availability and regulating translation of TOP motif-containing mRNAs, which mainly encode ribosomal proteins, through the 4E-BP repressor; this function is reported as resistant to rapamycin inhibition. The authors state that Lsp2, previously known as a storage protein, is also an adipose effector and feedback activator of mTORC1 in Drosophila. Lsp2 expression is induced by essential amino acids through mTORC1 and gated by additional signals of nutrient sufficiency.
Supporting source [1]
Lsp2 loss extends lifespan and lowers TOP translation
Genetic ablation of Lsp2 robustly extended lifespan without impairing key life history traits such as reproduction, according to the abstract. Translatomic profiling showed that loss of Lsp2 selectively reduced global TOP mRNA translation in a 4E-BP-dependent manner, thereby extending lifespan through a mechanism the authors describe as distinct from the effects of rapamycin.
Supporting source [1]
TOP motifs, 4E-BP and Drosophila scope
The authors report that TOP motifs co-emerged evolutionarily with 4E-BP and are present in nearly all Drosophila ribosomal protein mRNAs, and that the role of TOP motifs in translational control extends to Drosophila. They conclude that a nutrient-induced physiological factor amplifies mTORC1 output in TOP mRNA translation and regulates organismal longevity. These are findings in the fruit fly Drosophila, not evidence of human lifespan effects.
Supporting source [1]
How to interpret this
This explainer is based only on the abstract; the full text was not reviewed. The work is in Drosophila, so the lifespan and translation findings are not evidence of human lifespan benefits. The abstract does not report sample sizes, follow-up details or effect sizes.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Wang J, Cai Z, Gu J, Xiong S, Yi J, Yang M, Chang K, Ning X, Wen Y, Yan Y, Lu J, Wang Y, Zhai Z. · europepmc.org · September 23, 2026