Exalpha Biologicals, Inc.

Accelerating the Pace of Discovery
Exalpha Biologicals, Inc.

Microphthalmia Transcription Factor (MiTF)

  • Product Code: X1405M
  • Size: 100 µg
  • Price (USD): $438

Cat #

X1405M		 Quantity:      

Data Sheet

Product Name

Microphthalmia Transcription Factor (MiTF)









Product Type

Monoclonal Antibody


Human, Mouse, Rat


Gel Supershift, Western Blot, Immunoprecipitation, Immunohistochemistry (Frozen & Paraffin Sections)


Protein A/G Chromatography


100 µg

Price (USD)



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. 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. Mi is a basic helix-loop-helix-leucin zipper (b-HLH-ZIP) transtripotion 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' 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.

Positive Control

501 Mel human melanoma cells, wild-type human, rat, mouse osteoclast cells


Provided as solution in phosphate buffered saline with 0.08% sodium azide

Customer Storage

Product should be stored at -20ºC. Aliquot to avoid freeze/thaw cycles

Target Molecular Weight

52-56kDa doublet

Product Image

Image Legend

Immunohistochemical staining using microphthalmia antibody on formalin-fixed, paraffin embedded EWS/ATF1-induced tumor cells (scale bar 100 µm). (Image modified from original taken from product specific reference 2)

Database Links:



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 2. Hemesath P, et. al. MAP kinase links the transcription factor microphthalmia to c-Kit signalling in melanocytes. Nature. 1998, 391:298-301

Product Specific References

This product has been used in:

1. Tshori, S., et al, 'Transcription factor MITF regulates cardiac growth and hypertrophy' Journal of Clinical Investigation 2006, 116, , 2673-2681 2. Yamada, K., et al. 'EWS/ATF1 expression induces sarcomas from neural crest–derived cells in mice.' J. Clin. Invest., 123, 600-610 (2013) 3. Hagglund, A.-C., et al. 'Canonical Wnt/?-Catenin Signalling Is Essential for Optic Cup Formation.' PLoS One, 8, e81158 (2013) 4. Nakano, T., et al. 'Self-formation of optic cups and storable stratified neural retina from human ESCs.' Cell Stem Cell (2012) 10, 771-785