Phenotype Image Detail

Image

Caption

Trpm7 is temporally required for development of neural crest (NC)-derived pigment cells and dorsal root ganglion (DRG) sensory neurons. (A) Diagram showing unique pattern of Pax3-Cre expression in E10.5 NC. The cre transgene does not faithfully follow the endogenous Pax3 expression pattern and was not expressed in the upper (cervical and part of the thoracic) region of the NC. (B) Unique phenotype of Trpm7^tm1Clph/Trpm7^tm1Clph Tg(Pax3-cre)1Joe/0 (ko) mice (P2 or P12): loss of pigment only in the lower trunk and paresis of only the hind legs. (C) Absence of pigment cells only in the lower trunk of the ko mice. (Left) Haematoxylin and eosin (H&E) staining shows that pigment cells are present in the upper but not lower trunk in dorsal skin from a P12 ko mouse. (Right) Toluidine blue (T.B.) staining of P2 dorsal lumbar skin sections shows loss of pigment cells in the lower trunk of the ko mouse compared with wild-type (WT) littermate controls. (D) Immunohistochemistry of P2 dorsal lumbar skin sections confirmed the absence of microphthalmia-associated transcription factor (MiTF+) (Left) or DCT+ (Right) pigment cells in the lower trunk of ko mice. (E) Merged immunofluorescence and differential interference contrast (DIC) images show that Trpm7 was disrupted in both the upper and lower trunk of a P2 ko mouse, but the lower trunk had few DCT+ pigment cells and lacked pigment in comparison to the upper trunk. (F) (Upper) H&E staining of E18.5 lumbar spinal cord and DRG. (Lower) Loss of TRPM7 in large-diameter DRG sensory neurons in ko mice (immunofluorescence, P2 lumbar DRG).

Copyright

This image is from Jin J, Proc Natl Acad Sci U S A 2012 Jan 31;109(5):E225-33. Copyright 2012 National Academy of Sciences, U.S.A. J:181963

Associated Alleles

Symbol	Name
Tg(Pax3-cre)1Joe	transgene insertion 1, Jonathan A Epstein
Trpm7^tm1Clph	transient receptor potential cation channel, subfamily M, member 7; targeted mutation 1, David E Clapham

Associated Genotypes

Allelic Composition	Genetic Background
Trpm7^tm1Clph/Trpm7^tm1Clph Tg(Pax3-cre)1Joe/0	involves: 129S4/SvJae * C57BL/6 * SJL