TY - JOUR
T1 - Allocation and specification of the genital disc precursor cells in Drosophila
AU - Chen, Elizabeth
AU - Christiansen, Audrey E.
AU - Baker, Bruce S.
N1 - Funding Information:
We thank D. Bilder, K. Cadigan, M. Freeman, C. Goodman, S. Hayashi, J. Hooper, R. Johnson, T. Kornberg, M. Krasnow, K. Matthews, R. Nusse, R. Reuter, S. Sakonju, J. Simon, M. Scott, G. Struhl, T. Tabata, K. Wharton, and the Bloomington Stock Center for graciously providing reagents. We would also like to thank Baker lab members, J. H. Bayle, D. Pan, and our reviewers for their valuable comments and G. Bohm for fly food. This work was funded by a grant from the NIH to B.B.
PY - 2005/5/15
Y1 - 2005/5/15
N2 - The adult structures of Drosophila melanogaster are derived from larval imaginal discs, which originate as clusters of cells within the embryonic ectoderm. The genital imaginal disc is composed of three primordia (female genital, male genital, and anal primordia) that originate from the embryonic tail segments A8, A9, and A10, respectively, and produce the sexually dimorphic genitalia and analia. We show that the genital disc precursor cells (GDPCs) are first detectable during mid-embryogenesis as a 22-cell cluster in the ventral epidermis. Analysis of mutant and double mutant phenotypes of embryonic patterning genes in the GDPCs, together with their expression patterns in these cells, revealed the following with respect to the origins and specification of the GDPCs. The allocation of the GDPCs from the ventral epidermis requires the function of ventral patterning genes, including the EGF receptor and the spitz group of genes. The ventral localization of the GDPCs is further restricted by the action of dorsal patterning genes. Along the anterior-posterior axis, several segment polarity genes (wingless, engrailed, hedgehog, and patched) are required for the proper allocation of the GDPCs. These segment polarity genes are expressed in some, but not all of the GDPCs, indicating that anterior and posterior compartments are not fully established in the GDPCs. In addition, we found that the three primordia of the larval genital disc have already been specified in the GDPCs by the coordinated actions of the homeotic (Hox) genes, abdominal-A, Abdominal-B, and caudal. By identifying how these different patterning networks regulate the allocation and primordial organization of the 22 embryonic precursors of the compound genital disc, we demonstrate that at least some of the organization of the larval disc originates as positional information in the embryo, thus providing a context for further studies on the development of the genital disc.
AB - The adult structures of Drosophila melanogaster are derived from larval imaginal discs, which originate as clusters of cells within the embryonic ectoderm. The genital imaginal disc is composed of three primordia (female genital, male genital, and anal primordia) that originate from the embryonic tail segments A8, A9, and A10, respectively, and produce the sexually dimorphic genitalia and analia. We show that the genital disc precursor cells (GDPCs) are first detectable during mid-embryogenesis as a 22-cell cluster in the ventral epidermis. Analysis of mutant and double mutant phenotypes of embryonic patterning genes in the GDPCs, together with their expression patterns in these cells, revealed the following with respect to the origins and specification of the GDPCs. The allocation of the GDPCs from the ventral epidermis requires the function of ventral patterning genes, including the EGF receptor and the spitz group of genes. The ventral localization of the GDPCs is further restricted by the action of dorsal patterning genes. Along the anterior-posterior axis, several segment polarity genes (wingless, engrailed, hedgehog, and patched) are required for the proper allocation of the GDPCs. These segment polarity genes are expressed in some, but not all of the GDPCs, indicating that anterior and posterior compartments are not fully established in the GDPCs. In addition, we found that the three primordia of the larval genital disc have already been specified in the GDPCs by the coordinated actions of the homeotic (Hox) genes, abdominal-A, Abdominal-B, and caudal. By identifying how these different patterning networks regulate the allocation and primordial organization of the 22 embryonic precursors of the compound genital disc, we demonstrate that at least some of the organization of the larval disc originates as positional information in the embryo, thus providing a context for further studies on the development of the genital disc.
KW - Anterior/posterior patterning
KW - Dorsal/ventral patterning
KW - Genital disc precursor cells
KW - Homeotic genes
KW - Imaginal disc progenitor
KW - Primordia
KW - Segment polarity genes
UR - http://www.scopus.com/inward/record.url?scp=19344372868&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=19344372868&partnerID=8YFLogxK
U2 - 10.1016/j.ydbio.2005.02.032
DO - 10.1016/j.ydbio.2005.02.032
M3 - Article
C2 - 15893978
AN - SCOPUS:19344372868
SN - 0012-1606
VL - 281
SP - 270
EP - 285
JO - Developmental Biology
JF - Developmental Biology
IS - 2
ER -