IDENTIFICATION OF NOVEL FACTORS THAT REGULATE GNRH GENE-EXPRESSION AND NEURONAL MIGRATION

We used differential display PCR on two GnRH producing cell lines to i dentify genes involved in GnRH gene expression and neuronal migration. RNA from Gn10 cells (derived from a tumor in the olfactory area when GnRH neurons are migrating and make low levels of GnRH) and from GT1-7 cells (derived from a tumor in forebrain when GnRH neurons are postmi gratory and make high levels of GnRH) was reverse transcribed into cDN A. The cDNA was amplified using three anchored primers and eight rando m primers from each cell line and products from duplicate reactions el ectrophoresed in parallel in a denaturing acrylamide gel. Differential ly expressed cDNAs were excised, reamplified and used as probes in Nor thern analysis of total RNA from each cell line to confirm differentia lly expressed RNA. The cDNAs were sequenced and compared to the Genban k database. Four of five clones isolated from GT1-7 GnRH neurons are n ovel, while four of five clones isolated from Gn10 cells have homology to known DNA sequences. One clone, Gn8-01 encodes adhesion related ki nase (Ark), a molecule that has an N-terminal domain characteristic of cell adhesion molecules and whose kinase domain may play a role in pr otection from apoptosis. Together these data support the usefulness of the technique to identify novel genes that play a role in the control of GnRH expression and neuronal migration.