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Expr1872
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In late L2 larvae anti-PAG-3 staining was seen in approximately two dozen cells in the head, all six mechanosensory neurons, the BDU neurons, approximately ten cells in the tail as well as in the ventral cord. PAG-3 staining of many cells in the head and tail remained detectable in adult animals. In the ventral cord, PAG-3 was first detected in the Pn.aa neuroblasts. PAG-3 was not detected in the Pn.ap euroblasts or their descendants. PAG-3 was present equally in each of the descendant cells of Pn.aa after subsequent rounds of division (i.e. the Pn.aaa, Pn.aap, Pn.aaaa and Pn.aaap cells), including the three differentiating neurons generated by each Pn.aa neuroblast. In most cells, PAG-3 protein became undetectable shortly after the cells had been generated in the L1, but PAG-3 was present in six cells in the ventral cords of adults. In late L2 larvae anti-PAG-3 staining was seen in approximately two dozen cells in the head, all six mechanosensory neurons, the BDU neurons, approximately ten cells in the tail as well as in the ventral cord. PAG-3 staining of many cells in the head and tail remained detectable in adult animals. In the ventral cord, PAG-3 was first detected in the Pn.aa neuroblasts. PAG-3 was not detected in the Pn.ap neuroblasts or their descendants. PAG-3 was present equally in each of the descendant cells of Pn.aa after subsequent rounds of division (i.e. the Pn.aaa, Pn.aap, Pn.aaaa and Pn.aaap cells), including the three differentiating neurons generated by each Pn.aa neuroblast. In most cells, PAG-3 protein became undetectable shortly after the cells had been generated in the L1, but PAG-3 was present in six cells in the ventral cords of adults. PAG-3 expression persisted throughout the life of the animal in four cells in the retrovesicular ganglion at the anterior end of the ventral cord and in two cells in the posterior ventral cord. In newly hatched L1-stage larvae, before the initiation of the postembryonic W and P cell lineages, two cells in the retrovesicular ganglion expressed PAG-3. Based on position, these cells were most likely the RIG interneurons. After completion of the W and P cell lineages, two additional cells in the retrovesicular ganglion and two cells in the posterior ventral cord contained detectable PAG-3 protein. These nuclei might be the two AVF and the VA11 and VA12 neurons, respectively. This hypothesis was confirmed by staining animals carrying an integrated Punc-4lacZ reporter, which is expressed in the AVF and VA as well as other neurons, with PAG-3 antiserum and monoclonal antibody against beta-galactosidase. PAG-3 protein was expressed more widely in the nervous system than had been observed using the Ppag-3lacZ reporter. PAG-3 was detected during embryonic development in many nuclei ~280 minutes after fertilization. |
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