Identification of microphthalmia-associated transcription factor isoforms in dogs

Comparison of the homologous sequences for MITF isoforms among dogs and humans suggested that MITF-D, MITF-E and MITF-J may be expressed in canine adult tissues in addition to canine MITF-M, MITF-H, and MITF-A. However, RT-PCR showed that canine MITF-E and MITF-J, but not canine MITF-D were expressed. Although the mRNAs encoding canine MITF-H and MITF-A were expressed widely, MITF-M, MITF-E and MITF-J were expressed in tissue-specific patterns. Two types of mRNAs with and without an 18-base insert were detected for five MITF isoforms in canine tissues. MITF-M distal enhancer (MDE) was also located upstream from canine exon 1M.