
Swiatek PJ and Gridley T:
Perinatal lethality and defects in hindbrain development in mice
homozygous for a targeted mutation of the zinc finger gene Krox20.
Genes & Development 1993 Nov;7(11):2071-84
ABSTRACT
Krox20 is a zinc finger gene expressed in rhombomeres 3 and 5 during hindbrain development in vertebrates. Mice homozygous for a targeted
mutation that deletes the majority of the Krox20 genes, including
the zinc finger DNA-binding domain, died shortly after birth. The
primary phenotype of the homozygous mutant animals was the loss of
rhombomeres 3 and 5. This resulted in fusions of the trigeminal
ganglion with the facial and vestibular ganglia, and of the superior
ganglia of the glossopharyngeal and vagus nerves. These fusions
resulted in a disorganization of the nerve roots of these ganglia as
they entered the brain stem. These data demonstrate that Krox20
plays an essential role during development of the hindbrain and
associated cranial sensory ganglia in mice.