Phenotype Image Detail

Image

Caption

Fat1 loss of function alters shapes of selective facial and scapulohumeral muscles. Skeletal muscle groups were visualized in E14.5, E15.5, and E18.5 wild-type (WT) and Fat1^tm1.2Fhel/Fat1^tm1.2Fhel Tg(Myl1-lacZ)1Ibdml/0 (Fat1^{deltaTM/deltaTM} MLC3f-2E) fetuses, by X-gal staining. (A) Overview of the face and forelimb musculature at E14.5. Overall, constitutive ablation of Fat1 causes developmental abnormalities of muscle shape, affecting selective subcutaneous muscles in the face (Zyg, Min and Zyg maj, muscles, Occip. F, orbic. Or. and temporalis Muscles) and selective muscles in the scapulohumeral region. Muscle names are indicated. Muscles which are reduced or show an altered shape have their name underlined in mutant pictures. Ectopic muscles are indicated with red arrows. (B) Muscles of the scapulohumeral area at E14.5 and E15.5, visualized with dorsal views of the scapular muscles at E14.5, and side views of the forelimb at E15.5. Dorsal views reveal the reduced extent of the CM and Rhomboid muscles, and the abnormal connections between the upper and lower parts of the trapezius (amT and spT, respectively). A large additional ectopic muscle (red dotted line, bottom picture) is observed in the mutant embryo, that appears ectopically inserted between the spinodeltoid and Triceps brachii (LoTB and LaTb) muscles. (C) Analysis of muscles in the face at E14.5 (A), E15.5 (C, top), and at P0 (C, bottom), reveals abnormalities in shape, myofibre orientation and density in several subcutaneous muscles (red arrows) that occupy positions equivalent to that of human muscles of facial expression, while deeper muscles such as the masseters display normal shape. Overall the topography of muscles affected in Fat1 mutantmice resembles the map of muscles affected in human Facioscapulohumeral Dystrophy muscle in early phases of the disease. Muscle names abbreviations: amT: acromiotrapezius; amd: acromiodeltoid; Bra: brachialis; CM: cutaneous maximus; Ecu: Extensor carpi ulnaris;Ecr: Extensor carpi radialis; Edc: Extensor digitorum communis; Edl: extensor digitorum longus; Fr: Frontalis; LaTb: lateral Triceps Brachii; LoTb: Longitudinal Triceps Brachii; Occ: occipitalis; Orbic. Oc: orbicularis oculis; Orbic Or: Orbicularis Oris; Risor: Risorius (position equivalent to that of Risorius in human); SpD: spinodeltoid; SpT: spinotrapezius; SpTS: Subcutaneous part of the Spinotrapezius muscle; Temp: Temporo-parietal muscle; Zyg: Zygomaticus (position inferred from equivalent position in human).

Copyright

This image is from Caruso N, PLoS Genet 2013 Jun;9(6):e1003550, and is displayed under the terms of the Creative Commons Attribution 4.0 International License. J:199157

Associated Alleles

Symbol	Name
Fat1^tm1.2Fhel	FAT atypical cadherin 1; targeted mutation 1.2, Francoise Helmbacher
Tg(Myl1-lacZ)1Ibdml	transgene insertion 1, Developmental Biology Institue of Marseilles-Luminy

Associated Genotypes

Allelic Composition	Genetic Background
Fat1^tm1.2Fhel/Fat1^tm1.2Fhel Tg(Myl1-lacZ)1Ibdml/0	involves: 129S6/SvEvTac * BALB/cJ * C57BL/6J * SJL