3.7 Gene expression analysis in protein processing signaling pathways
In DEG-enriched pathways, up-regulated expression of male prawn genes associated with protein processing in the endoplasmic reticulum play an important role in protein folding and misfolded protein elimination in both the brain (Figure 9A) and thoracic ganglion (Figure 9B). In fact, male prawns showed faster growth than females, and more proteins needed to be assembled. In turn, more misfolded protein needed to be eliminated in order to escape concentrations exceeding to the threshold of proteotoxic stress. 435 genes were identified as participating in pathways of protein processing in the endoplasmic reticulum (Table S1). Principle component analysis (PCA) separated these genes expressed in the brain and thoracic ganglion of males and females into different principal components. The first and second principal components accounted for 40.9% and 36.2% of the variation between the sexes (Figure 9C). Of 42 DEGs between the prawn sexes, 21 male genes had up-regulated expression in the brain and 26 had up-regulated expression in the thoracic ganglion compared with the female genes. A total of 38 DEGs were obtained from male prawns, and 39 DEGs from female prawns (Figure 9D). These DEGs, shown in a heat map, supported the results of the PCA analysis.