Conserved usage of gap and homeotic genes in patterning the CNS

Current Opinion in Neurobiology

Volumn 9, Issue 5, 1999, Pages 589-595

  Reichert, Heinrich ^a   Simeone, Antonio ^b  

^a UNIVERSITY OF BASEL   (Switzerland)

^b INSTITUTE OF GENETICS AND BIOPHYSICS ADRIANO BUZZATI TRAVERSO   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

BRAIN DEVELOPMENT; CENTRAL NERVOUS SYSTEM; DROSOPHILA; EMBRYO DEVELOPMENT; GENE FUNCTION; HOMEOBOX; INVERTEBRATE; MOLECULAR EVOLUTION; MOUSE; NONHUMAN; PRIORITY JOURNAL; REVIEW; SEQUENCE HOMOLOGY; VERTEBRATE;

EID: 0032873404     PISSN: 09594388     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0959-4388(99)00002-1     Document Type: Review

References (71)

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70. -/- null mutant mice rescues epilepsy and abnormalities affecting corticogenesis and eye development, but does replace the missing lateral semicircular duct. These findings are very similar to those obtained by replacing Otx1 with the Drosophila otd and strongly support the idea that with the exception of the inner ear, the contrasting phenotypes of Otx1 and Otx2 null mutant mice stem from differences in expression patterns rather than from differences in amino acid sequences. Moreover, these findings strongly suggest that the ability to specify the lateral semicircular duct of the inner ear is an Otx1-specific property.
71. -/- null mutant mice causes the recovery of the anterior neural plate and proper gastrulation but fails to maintain fore-midbrain identities, displaying a headless phenotype from 9 d.p.c. onwards. Unexpectedly, in spite of the RNA distribution in both the visceral endoderm (VE) and epiblast, the OTX1 protein was synthesized only in the VE. This VE-restricted translation was sufficient to recover Otx2 requirements for specification of the anterior neural plate and proper organization of the primitive streak, thus providing evidence that the difference between Otx1 and Otx2 null mice phenotypes originates from their divergent expression patterns. Moreover, these data suggest that the differential post-transcriptional control existing between VE and epiblast cells may contribute to fundamental regulatory mechanisms required for head specification.