A RAINBOW-TROUT SRY-TYPE GENE EXPRESSED IN PITUITARY-GLANDS

A Sox (SRY-type HMG box) gene, designated SoxP1, was isolated from a c DNA library made from pituitaries of immature rainbow trout, Sequence analysis indicated that the cDNA had an open reading frame encoding 46 7 amino acid residues containing a DNA binding motif, known as the hig h mobility group (HMG) box, Northern blot analysis showed trout SoxP1 mRNA was detected in pituitaries and gonadal tissues, but not in liver , spleen, and heart, In pituitaries, trout SoxP1 mRNA was more abundan t in immature fish than in mature fish, Gel shift retardation analysis indicated that the recombinant HMG box protein of SoxP1 produced in E , coli had a DNA binding property for an AACAAT or AACAAAG sequence, T hese findings suggest that the trout SoxP1 protein may play certain ro les in growth or maturation in pituitaries as a transcription factor.