Transcriptional silencing of vitellogenesis-inhibiting hormone (VIH) subtype-I in the whiteleg shrimp, Litopenaeus vannamei

Eyestalk ablation, which is a method for the removal of the source of vitellogenesis-inhibiting hormone (VIH), is frequently used in Litopenaeus vannamei in order to stimulate ovarian maturation and spawning in captivity. In this study, we assessed the effects of vih silencing using double-stranded RNA (dsRNA) in L. vannamei females. The relative expression levels of vitellogenin (vg) and vih were analyzed in the ovary and eyestalks, respectively, and levels of Vg and VIH in hemolymph were quantified at 10 and 20 days following injection with VIH-dsRNA, green fluorescent protein (GFP)-dsRNA (a non-VIH-related dsRNA), or Tris-EDTA (TE) buffer. Expression of vih in the eyestalks was significantly suppressed at 10 and 20 days after VIH-dsRNA injection. Hemolymph VIH levels were significantly increased at 10 days after VIH-dsRNA injection and then decreased to initial levels. However, there were no significant differences in the levels of Vg in hemolymph or vg mRNA in the ovary.