| 14048 |
P97767 |
EYA1_MOUSE |
Eyes absent homolog 1 (EC 3.1.3.16) (EC 3.1.3.48) |
DISRUPTION PHENOTYPE |
Complete perinatal lethality in homozygotes, due to severe craniofacial and skeletal defects, combined with an absence of thymus, kidneys, parotid glands and ears. Mice present multiple skeletal defects in skull, neck, rib and pelvic girdle, but no major defects in muscle development. Otic anomalies involve the inner, middle and outer ears, with malformed auricles and eardrums, malformations of the incus, malleus, and stapes, while the tympanic cavity never formed. Likewise, mice display an absence of inner ear structures. Heterozygotes present milder symptoms with low penetrance, including renal defects, similar to human BOR (branchio-oto-renal) syndrome. Increased apoptosis and loss of renal tubules seen in the developing kidney with increased immunostaining for 'Ser-139' phosphorylated H2AX. Mice lacking both Six1 and Eya1 show defects in kidney development, complete absence of hypaxial muscle, severe reduction in epaxial muscle and a 5-10-fold by volume smaller pituarity than the wild-type gland. Mice lacking both Eya1 and Eya2 display complete embryonic lethality, due to severe defects in muscle development, including the absence of a diaphragm and of ventral hypaxial muscles of the trunk and the complete absence of muscles in forelimbs and hindlimbs, similar to the phenotype of mice lacking both Six1 and Six4. While Six1 is normally expressed in these mice, it does not active transcription from cognate promoter elements, and does not activate transcription of Pax3. {ECO:0000269|PubMed:10471511, ECO:0000269|PubMed:14628042, ECO:0000269|PubMed:17098221, ECO:0000269|PubMed:19234442}. |