Neuronal expression of chimeric genes in transgenic mice.
Gene expression may occur in unexpected ectopic sites when diverse genetic elements are juxtaposed as chimeric genes in transgenic mice. To determine the specific contribution of the promoter and reporter gene in ectopic expression, we have analyzed the expression of 14 different fusion genes in transgenic mice. Chimeric genes containing the mouse metallothionein-I promoter linked to either the rat or human growth hormone gene or the calcitonin/CGRP gene are expressed in a very similar pattern of neuronal regions. This ectopic expression is not a unique feature of the metallothionein promoter, since transferring the human growth hormone gene to four other heterologous promoters resulted in varying degrees of ectopic expression in overlapping subsets of cortical and hypothalamic neurons. The novel pattern of ectopic expression suggests that these otherwise unrelated neurons share a common developmental regulatory machinery for activation of gene transcription.
Russo
A F
AF
Center for Molecular Genetics and Eukaryotic Regulatory Biology Program, University of California, San Diego, La Jolla 92093.
Crenshaw
E B
EB
Lira
S A
SA
Simmons
D M
DM
Swanson
L W
LW
Rosenfeld
M G
MG
D000818:Animals; D002116:Calcitonin / Q000235:genetics; D015740:Calcitonin Gene-Related Peptide / Q000235:genetics; D002678:Chimera; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D005796:Genes; D013006:Growth Hormone / Q000235:genetics; D008668:Metallothionein / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D011401:Promoter Regions, Genetic; D015347:RNA Probes
D015347:RNA Probes; D013006:Growth Hormone; D002116:Calcitonin; D008668:Metallothionein; D015740:Calcitonin Gene-Related Peptide