Midkine gene and the m4 muscarinic acid receptor gene are linked on mouse chromosome 2

The retinoid acid inducible midkine gene encodes a highly basic, heparin-binding protein that possesses potential functions of growth or differentiation during the early stages of mouse embryonic development. Midkine gene has been mapped to mouse Chromosome 2. Here we report that the midkine gene is located in close proximity to the m4 muscarinic acid receptor gene. M4 codes for a transmembrane G protein that functions to transduce the action of acetylcholine neural transmitters in the nervous system, The two genes have the directions of their transcriptions running toward one another, and the distance between their respective 3' ends is approximately 1.3 kb. (C) 1996 Academic Press, Inc.