By fluorescent differential display, we identified six transcripts (CAPS2/Cadps2, Cdh22, b1402, c1502, d1401, and d1501) that showed the differential expression patterns during the postnatal development of the mouse cerebellum. We further analyzed the latter four transcripts whose cellular localizations in developing mouse brains have not been studied. In the postnatal cerebellum, clones c1502 and d1501 were transiently up-regulated; clone b1402 was up-regulated; and clone d1401 remained relatively constant. Sequence analysis revealed that d1401 and c1502 were derivatives of Ogdh (oxoglutarate dehydrogenase) and QP-C (ubiquinol-cytochrome c reductase complex ubiquinone-binding protein), respectively. Moreover, b1402 and d1501 were identified as transcripts of a predicted gene (4933409K07Rik) and a novel EST, respectively. b1402 and d1501 were abundantly present in the cerebellum, whereas c1502/QP-C and d1401/Ogdh were widely distributed in various mouse tissues. In the postnatal mouse brain, moderately high mRNA levels of b1402 were restricted to the olfactory bulb, striatum, cerebral cortex (layers II-III and VI), hippocampus (dentate granule cells), and cerebellum (granule cells). c1502/QP-C mRNA was localized at high levels in the olfactory bulb, cerebral cortex, hippocampus, thalamus (anterodorsal nucleus, parafacicularis nucleus), tegmentum (red nucleus), cerebellum (Purkinje and granule cells), and pons (pontine nucleus, reticulotegmental nucleus, trapezoid body, vestibular nucleus). High mRNA levels of d1401/Ogdh were observed in the olfactory bulb, hippocampus, cerebellum, and pons, whereas those of d1501 were detected in the granule cells of the olfactory bulb, dentate gyrus, and cerebellum.