Production of insulin by pancreatic β-cells.

<p>A) Quantitative RT-PCR of insulin mRNA in the pancreas from wild-type and mutant mice. Total RNA was isolated at E18.5 and transcribed into cDNA. When normalized to the expression of RpS9, there was no difference in insulin expression between samples from wild-type, homozygous knock-in and homozygous knock-out samples. The bars give the mean of triplicate measurements with standard deviation. B) Localization of insulin in islets of the pancreas from E18.5 mice. Paraffin sections of the pancreas from wild-type, homozygous knock-in and homozygous knock-out mice were incubated with a monoclonal antibody against murine insulin, followed by a rhodamine-labeled secondary antibody. No qualitative difference was noted between samples from wild-type and mutant mice. Bars = 100 µm.