RESUMO
Congenital cranial dysinnervation disorders (CCDD) encompass a number of related conditions and includes Duane syndrome, congenital fibrosis of the external ocular muscles, Möbius syndrome, congenital ptosis and hereditary congenital facial paresis. These are congenital disorders where the primary findings are non-progressive and are caused by developmental abnormalities of cranial nerves/nuclei with primary or secondary dysinnervation. Several CCDD genes have been found, which enhance our understanding of the mechanisms involved in brain stem development and axonal guidance.
Assuntos
Doenças dos Nervos Cranianos/congênito , Doenças dos Nervos Cranianos/diagnóstico , Doenças dos Nervos Cranianos/genética , Síndrome da Retração Ocular/diagnóstico , Síndrome da Retração Ocular/genética , Paralisia Facial/congênito , Paralisia Facial/diagnóstico , Paralisia Facial/genética , Fibrose , Genes Homeobox/genética , Predisposição Genética para Doença , Humanos , Síndrome de Möbius/diagnóstico , Síndrome de Möbius/genética , Mutação , Músculos Oculomotores/patologiaRESUMO
Receptor-like protein tyrosine phosphatases potentially play a crucial role in axon growth and targeting. We focus here on their role within the embryonic avian spinal cord, in particular the development and outgrowth of motorneurons. We have used in situ mRNA hybridization to examine the spatiotemporal expression of eight receptor-like protein tyrosine phosphatases and find that it is both dynamic and highly varied, including novel, isoform-specific expression patterns. CRYP alpha 1 is expressed in all of the ventral motorneuron pools, whereas CRYP2, RPTP gamma, and RPTP alpha are only expressed in specific subsets of these neurons. CRYP alpha 2, RPTP psi, and RPTP delta are neuronally expressed elsewhere in the cord, but not in ventral motorneurons, whereas RPTP mu is unique in being restricted to capillaries. The developmentally regulated expression of these genes strongly suggests that the encoded phosphatases play numerous roles during neurogenesis and axonogenesis in the vertebrate spinal cord.
