Identification, characterisation, and gene expression analysis of GFAP in the brain of red-bellied pacu, Piaractus orinoquensis

Glial fibrillary acidic protein (GFAP) is considered a signature marker for astrocytes in several species, due to its role in cell integrity and signalling. This study aimed at the molecular characterisation of GFAP cDNA from Piaractus orinoquensis and to assess the gene expression in an acute brain injury model. The nucleotide sequence of gfap was obtained from cDNA nanosequencing and full open reading frame was amplified and confirmed by sanger sequencing. Relative gene expression was assessed in fish tissues and in the brain under an acute injury by qPCR. Western blot analysis was performed for the detection of GFAP in the brain. GFAP from Piaractus orinoquensis showed conserved regions and domains and GFAP transcripts were detected in all tissues. In the acute brain injury model, there was a downregulation of GFAP mRNA level as well as for пHIF-1a and GlucoR two hours post-injury. The study of the inflammatory response modulated by astrocytes will help to understand the regulatory mechanisms in the central nervous system and the development of a piscine bio model for human and animal neuropathology. This is the first report of the full open reading frame of red-bellied pacu GFAP cDNA.