Disentangling the aging gene expression network of termite queens

Area of Science:

• Gerontology
• Insect Biology
• Molecular Biology

Background:

• Social insects, like termites, have exceptionally long lifespans compared to most insects, making them valuable models for aging research.
• Aging studies in social insects are limited by a lack of quantitative lifespan and gene expression data.
• This study investigates aging in drywood termite (Cryptotermes secundus) queens.

Purpose of the Study:

• To determine age-dependent survival probabilities in termite queens over 15 years.
• To perform transcriptome analyses across the entire lifespan of known-age queens.
• To understand the molecular mechanisms underlying aging in long-lived social insect reproductives.

Main Methods:

• Longitudinal survival analysis of Cryptotermes secundus queens over 15 years.
• Time-course transcriptome sequencing and co-expression network analysis.
• Analysis of gene expression patterns related to epigenetic control, transposable elements, and proteostasis.

Main Results:

• Cryptotermes secundus queens have a median maximum longevity of 11.0 years (max 13 years).
• Aging was non-gradual, with significant gene network changes occurring after ten years, indicating physiological upheaval.
• Upregulation of protein synthesis, degradation, and autophagy suggests a late-life stress response involving the cnc transcription factor.

Conclusions:

• Termite queens experience non-linear senescence with a late-life physiological crisis.
• Proteostasis network alterations and stress responses are critical components of aging in social insect queens.
• These molecular changes precede the queens' demise, offering insights into extreme longevity.