Abstract
Pituitary organogenesis is modulated by temporal and special expression of various genes at the fetal stage. Suppressive subtraction cloning was employed to search for genes expressed during porcine fetal pituitary development. The variations in the genes expressed in the pituitaries on fetal days 40 and 110, respectively, were analyzed by subtraction with the inverted combination. Genes encoding growth arrest specific-2, coated vesicle membrane protein, steroid membrane binding protein, putative protease cancer tumor suppressor, secretogranin, calumenin and others exhibited elevated expression during pituitary development, in addition to genes encoding GH, prolactin and glycoprotein hormone common α subunit. Concomitantly, we also found a gene that encodes a porcine ortholog of c-myc transcription factor and determined its entire nucleic acid sequence. On the other hand, histone H3.3B, GTP-binding α-stimulatory subunit, stathmin and others were found as gene expression decreased. Thus, the expression levels of many genes change during pituitary development.