UNASSIGNED: During development, HOX genes play critical roles in the establishment of segmental differences. In the @entity238 central nervous system, these differences are manifested in the number and type of neurons generated by each neuroblast in each segment. HOX genes can act either in neuroblasts or in postmitotic cells, and either early or late in a lineage. Additionally, they can be continuously required during development or just at a specific stage. Moreover, these features are generally segment-specific. Lately, it has been shown that contrary to what happens in other tissues, where HOX genes define domains of expression, these genes are expressed in individual cells as part of the combinatorial codes involved in cell type specification. In this report we analyse the role of the Bithorax-complex genes - Ultrabithorax, @entity4534 and @entity4533 - in sculpting the pattern of crustacean cardioactive peptide (CCAP)-expressing neurons. These neurons are widespread in invertebrates, express CCAP, @entity40658 and MIP neuropeptides and play major roles in controlling ecdysis. There are two types of CCAP neuron: interneurons and efferent neurons. Our results indicate that Ultrabithorax and @entity4534 are not necessary for specification of the CCAP-interneurons, but are absolutely required to prevent the @entity204 by apoptosis of the CCAP-efferent neurons. Furthermore, @entity4533 controls by repression the temporal onset of neuropeptide expression in a subset of CCAP-efferent neurons, and a peak of @entity4080 hormone at the end of larval life counteracts this repression. Thus, Bithorax complex genes control the developmental appearance of these neuropeptides both temporally and spatially.

The study of the Bithorax-complex genes in patterning CCAP neurons reveals a temporal control of neuronal differentiation by XXXX .

@entity40658 :: ('42560(Tax:7227)', 'Gene') :: ['Bursicon'] @entity4534 :: ('42037(Tax:7227)', 'Gene') :: ['abdominal-A', 'Abdominal-A'] @entity4533 :: ('47763(Tax:7227)', 'Gene') :: ['Abdominal-B'] @entity4080 :: ('MESH:D004440', 'Chemical') :: ['ecdysone'] @entity204 :: ('MESH:D003643', 'Disease') :: ['death'] @entity238 :: ('7227', 'Species') :: ['Drosophila']
@entity4533 :: (47763(Tax:7227),Gene) :: ['Abd-B']
