Human cellubrevin is expressed in many human tissues. The Northern blot containing 2 μg of poly A⁺ mRNA from the indicated human tissues was incubated with a [³²P] nick-translated DNA probe made from the 292-bp of the 3′ untranslated region of human cellubrevin (bp 402-693, Fig 1A). The blot was washed and exposed to film for 18 hours at −80°C with an intensifying screen. The positions of the size standards in kilobases are shown at right. The same blot was also probed with a [³²P] nick-translated β-actin DNA probe, washed, and exposed to film at −80°C for 2 hours. Some tissues contain two isoforms that will hybridize with the β-actin probe (pancreas and placenta).