Mouse anti Human Microphthalmia Transcription Factor (MiTF)

There are two known isoforms of MiTF differing by 66 amino acids at the NH2 terminus. Shorter forms are expressed in melanocytes and run as two bands at 52kDa and 56kDa, while the longer Mi form runs as a cluster of bands at 60-70kDa in osteoclasts and in B16 melonoma cells (but not other melanoma cell lines), as well as mast cells and heart. It reacts with both melanocytic as well as the non- melanocytic isoforms of MiTF. This Ab does not cross-react with other b-HLH-ZIP factors by DNA mobility shift assay. MiTF is a basic helix-loop-helix-leucin zipper (b-HLH-ZIP) transcription factor implicated in pigmentation, mast cells and bone development. The mutation of MiTF causes Waardenburg Syndrome type II in Humans. In mice, a profound loss of pigmented cells in the skin eye and inner ear results, as well as osteopetrosis and defects in natural killer and mast cells. These melanocyte isoforms have been shown by two dimensional tryptic mapping to differ in c-Kit-induced phosphorylation. Osteopetrotic rat strain harbors a large genomic deletion encompassing the 3 prime half of MiTF including most of the b-HLH-ZIP region. Osteoclasts from these animals lack MiTF protein in contrast to wild-type rat, mouse, and Human osteoclasts.

Hybridoma produced by the fusion of splenocytes from RBF/DnJ mice immunized with an N-terminal fragment of Human microphthalmia protein and mouse myeloma NS1 cells.

This antibody can be used for gel supershift assays, immunoprecipitation (2 µg/mg of protein lysate), Western blotting (1 µg/mL) and immunohistochemistry on frozen and formalin fixed, paraffin embedded tissue sections. Optimal concentration should be evaluated by serial dilutions._x000D_ In Western blotting, it recognizes a doublet of 52-56kDa, identified as serine-phosphorylated and unphosphorylated forms of melanocytic isoforms of microphthalmia (Mi) transcription factor.

This product is intended FOR RESEARCH USE ONLY, and FOR TESTS IN VITRO, not for use in diagnostic or therapeutic procedures involving Humans or animals.

1. Weilbaecher KN, et. al. Age-resolving osteopetrosis: a rat model implicating microphthalmia and the related transcription factor TFE3. J. Exp.Med. 1998, 187: 775-785_x000D_ 2. Hemesath P, et. al. MAP kinase links the transcription factor microphthalmia to c-Kit signalling in melanocytes. Nature. 1998, 391:298-301