Expression of the MUC 6 mucin gene in development of the human kidney and male genital ducts

The MUC 6 mucin cDNA was isolated from a human stomach cDNA library and has been shown to be expressed in a number of other tissues in the gastrointes tinal tract, including the gallbladder, pancreas, and parts of the ileum an d colon. Here we establish that MUC 6 is expressed transiently in the nephr ogenic zone of the kidney in the early midtrimester of development. MUC 6 t ranscripts were detected in the epithelium of ureteric buds at 13 weeks and at lower levels from 17 to 23 weeks of gestation. Traces of MUC 6 mRNA wer e seen in the collecting ducts but not elsewhere in the developing kidney, and MUC 6 glycoprotein was detected in the epithelium of ureteric buds and collecting ducts. MUC 6 transcripts were absent from adult kidney. This pat tern of expression of MUC 6 in the developing kidney suggests a role in epi thelial organogenesis. MUC 6 transcripts were also present at low levels in mid-trimester epididymal epithelium.