Related Experiment Video
Updated: Sep 15, 2025
05:34
Sexual Crosses with the Mucoromycete Phycomyces blakesleeanus
Published on: June 6, 2025
239
Endosymbionts interacting with sex-determining genes and processes
Laura C Fricke1, Matthew D Villalta1, Amelia Ri Lindsey1
1Department of Entomology, University of Minnesota, 1980 Folwell Ave, St Paul, MN 55108, USA.
Current Opinion in Insect Science
|July 14, 2025
Summary
Maternally inherited insect symbionts manipulate host reproduction, skewing sex ratios to favor females. Researchers are identifying microbial proteins that cause male-killing, parthenogenesis, and feminization, revealing insights into insect diversity.
Area of Science:
- * Microbiology and Evolutionary Biology
- * Insect Reproductive Biology
Background:
- * Insects exhibit remarkable reproductive diversity, often influenced by maternally inherited symbionts.
- * These symbionts have evolved mechanisms to enhance host fitness and manipulate insect sex ratios, typically favoring females.
- * Maternal inheritance has driven the selection of specific microbial strategies for symbiont transmission and host manipulation.
Purpose of the Study:
- * To characterize the genetic and cellular mechanisms by which maternally transmitted symbionts manipulate insect sex determination.
- * To identify specific microbial effector proteins responsible for phenotypes like male-killing, parthenogenesis, and feminization.
- * To explore the evolutionary convergence of these symbiont-host interactions.
Main Methods:
- * Identification of microbial effector proteins involved in sex ratio manipulation.
- * Analysis of host genetic and cellular processes targeted by symbiont effectors, including dosage compensation and sex determination pathways.
- * Comparative studies across diverse insect models and non-model organisms.
Main Results:
- * Specific microbial effector proteins have been identified that induce male-killing, parthenogenesis, and feminization in various insects.
- * Many of these effectors target conserved host processes, such as dosage compensation and the sex determination cascade involving genes like transformer and doublesex.
- * The independent evolution of these symbionts and their associated phenotypes provides a framework for studying convergent evolution.
Conclusions:
- * Maternally inherited symbionts possess sophisticated mechanisms to manipulate insect reproduction and sex ratios.
- * Convergent evolution is evident in the independent origins of symbionts inducing similar reproductive manipulation phenotypes.
- * Understanding these microbial effectors offers insights into the fundamental mechanisms driving insect reproductive diversity and evolution.
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