[Chromogranin A gene antisense transgenic mice and the tissue specific promoter of chromogranin A gene].

The vector pGAS1C-lacZ was constructed which contains cga promoter-lacZ and cga promoter-cga antisense cDNA two major parts. The pGAS1C-lacZ was integrated into genome of PC-12 cells and lacZ gene expressed in PC-12 cells. We cut the pGAS1C-lacZ with Xba I and Sal I to get rid of the framework of plasmid pGAS1C-lacZ, then microinjected the other part which contains antisense DNA into female pronucleus of the fertile mouse eggs. All injected fertile eggs were transplanted into the oviduct of foster so that the injected eggs developed normally. We selected transgenic mice by PCR, and got 14 transgenic founders. The founders were hybridized with normal mice respectively to reproduce the offspring F1 of founders. We executed all the founders and took their adrenal glands to dye with X-Gal respectively. Paraffin sections of the dyed adrenal glands were used to determine the level of lacZ expression in transgenic mice, so we selected two founders which adrenal glands were dyed deeply, and remained their offsprings. Taking different tissues from the transgenic mice to dye with X-Gal respectively, and we found the lacZ gene expressed in the adrenal gland and pancreas, but not in the muscle and adipose tissues. This result shows the neuroendocrine tissue specific promoter of Chromogranin A gene.