Beetle Sexes Differ in microRNA Expression
Researchers at the University of Giessen, Germany provide for the first time information about miRNAs in T. castaneum exhibiting differential- and gender-specific expression pattern upon exposure to different stressors. Whether these changes translate into environmentally induced heritable epigenetic changes remains to be elucidated.
They used miRNA microarray and found that Tribolium exhibits both gender- and stressor-specific adjustment of immune gene and miRNA expression. Strikingly, they discovered that the number of stressor-induced miRNAs in females is remarkably higher than in males. This observation could support the hypothesis called Bateman’s principle in immunity that predicts gender-specific immune responses because females gain fitness through increased longevity, whereas males gain fitness by increasing mating rates. These results suggest that males and females display differential regulatory elements, both pre- and post-transcriptional, likely resulting from different investment strategies in life-history traits.