Effects of severe hypoxia and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knock-down on its gene expression, activity, subcellular localization, and apoptosis in gills of the shrimp Penaeus vannamei

ABSTRACT

Penaeus vannamei, experiences hypoxia in its natural habitat and in aquaculture. Under hypoxia, cells enhance anaerobic energy production through glycolysis dependent on the up-regulation of glycolytic enzymes including glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in gills. In vertebrates, GAPDH translocates into the nucleus and displays “moonlighting” functions including apoptosis. These alternative localizations and functions have not been described in crustaceans. We examined the effect of severe hypoxia and GAPDH silencing by RNA interference (RNAi) on its mRNA expression localization and glycolytic activity in P. vannamei gills. Expression and cytosolic activity were up-regulated only in hypoxia-exposed shrimp, but not in hypoxia-silenced specimens. GAPDH was immunodetected in cytosol and nucleus regardless of oxygen conditions. Hypoxia and RNAi decreased activity in cytosol and nucleus without affecting protein abundance, which suggests that nuclear GAPDH may have non-glycolytic functions. Moreover, Caspase-3 (Casp-3) expression increased with GAPDH silencing, suggesting alternative roles for GAPDH in apoptosis evasion.  

KEYWORDS:

• Penaeus vannamei
• hypoxia
• GAPDH
• Caspase-3
• RNAi
• cell fractionation

Acknowledgments

We thank Biol. Adrian Gamez-Alejo, Guadalupe Cota and Elizabeth Cota from the Laboratory of Marine Invertebrates Physiology at CIAD for their technical support in shrimp experiments. We also thank Dr. José Angel Huerta for his help in Western blot densitometric analysis. LCJ had a postdoctoral fellowship from CONACyT. ABT is a Ph.D. student at Scripps Institution of Oceanography-UCSD.

Disclosure statement

No potential conflict of interest was reported by the authors.

Author’s contributions

LCJ, MT, and GYP conceived and designed the experiments. LCJ, LLC, and ABPU performed the experiments and analyzed the data. ABT and MT performed and analyzed the immunostaining assays. SGJ coordinated the shrimp maintenance and biological assay. LCJ drafted the manuscript. GYP and MT edited the manuscript. All the authors reviewed and approved the final version of the manuscript.

Supplemental data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10236244.2023.2216346

Additional information

Funding

This work was supported by UC-MEXUS CONACyT grant CN-18-108 to MT and GYP) and CONACyT Ciencia Básica grant A1-S-24557 to GYP.