Silencing of the hypoxia inducible factor 1-HIF-1-obliterates the effects of hypoxia on glucose and lactate concentrations in a tissue-specific manner in the shrimp Litopenaeus vannamei

Many molecular and physiological responses to hypoxia are controlled by the transcription factor called hypoxia inducible factor 1 (HIF-1). Metabolic responses are particularly important for marine crustaceans that suffer hypoxia in their aquatic environment, including shrimp. HIF-1 is a heterodimer recently described in shrimp and composed by alpha and beta subunits. In the present study, we investigated the effect of silencing HIF-1 using dsRNA in the response to hypoxia in the shrimp Litopenaeus vannamei in vivo. Intramuscular injection of dsRNA for alpha and beta separately, decreased the concentration of the corresponding transcripts in gills from shrimp maintained in normoxia, while no effect was detected in muscle. In contrasts, during hypoxia, silencing of HIF-1 alpha or HIF-1 beta, did affect the corresponding transcripts. Moreover, silencing of the alpha and beta subunits of HIF-1 affected the concentrations of glucose and lactate in hemolymph and gills from shrimp exposed to hypoxic conditions, giving insights of the action of HIF-1 in these responses. (C) 2010 Elsevier B.V. All rights reserved.