Differential expression of two glucocorticoid receptors in seabass (teleost fish) head kidney after exogeneous cortisol inoculation.
Stressful conditions include a prompt release of corticosteroid hormones which can mediate gene expression through glucocorticoid receptors (GR). Since two seabass (Dicentrarchus labrax) GRs have been cloned and sequenced from peritoneal cavity cells (DlGR1) and liver (DlGR2), a comparative amino acid sequence analysis that included Haplochromis burtoni HbGRs, was carried out and homologies disclosed. The DlGR1 and DlGR2 deduced aminoacid sequences showed 61% identity (I) and 70% similarity (S). Moreover, DlGR2 was similar to HbGR2b (69% I, 73% S), and the DlGR1 to HbGR1 (72% I, 78% S). In addition, we examined the expression of the DlGRs after exogeneous cortisol inoculation into the peritoneal cavity, mimicking stress effects. At various times after the administration (3 h, 24 h, 1 week), gene expressions was evaluated in head kidney by real-time PCR. In addition, immunoblotting and densitometry analyses were performed with anti-DlGR1 antibodies. Although sea bass head kidney expressed both DlGR1 and DlGR2 they were differentially modulated by intraperitoneal implant of exogeneous cortisol.
Vazzana
Mirella
M
Laboratory of Marine Immunobiology, Department of Animal Biology, University of Palermo, Via Archirafi, 18 Palermo, Italy.
Vizzini
Aiti
A
Sanfratello
Maria Antonietta
MA
Celi
Monica
M
Salerno
Giuseppina
G
Parrinello
Nicolò
N
D000818:Animals; D001492:Bass / Q000033:anatomy & histology* / Q000235:genetics*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D006854:Hydrocortisone / Q000097:blood / Q000494:pharmacology*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000737:chemistry / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D011965:Receptors, Glucocorticoid; D006854:Hydrocortisone