... shapes to fit each other. Here we found that, in the development of ball-and-socket joints in the Drosophila leg, the two sides of ECM form sequentially. We show that distinct cell populations produce the ‘ball’ and the ‘socket’, and that these cells undergo extensive shape changes while depositing ECM...

...Daniel J. McKay; Carlos Estella; Richard S. Mann Limb development requires the elaboration of a proximodistal (PD) axis,which forms orthogonally to previously defined dorsoventral (DV) and anteroposterior (AP) axes. In arthropods, the PD axis of the adult leg is subdivided into two broad domains...

... of strong dachs mutations, report the cloning of the dachs gene, characterize the localization of Dachs protein, and investigate the relationship between Dachs and the Fat pathway. Mutation of dachs reduces, but does not abolish, the growth of legs and wings. dachs encodes an unconventional myosin...

... ; Caubit et al., 1999 ; Davis et al., 1999 ; Davis et al., 2001a ; Davis et al., 2001b ; Hammond et al., 1998 ; Kohlhase et al., 1998 ). Thus, it is possible that these genes are evolutionarily conserved Dll/Dlx targets. Several genes lie genetically downstream of Dll in the developing leg...

... this response specificity. We have analysed the specification of bract cells in Drosophila legs. We observed that mechanosensory bristles induced bract fate in neighbouring epidermal cells, and that the RAS/MAPK pathway mediated this induction. We have identified Spitz and EGFr as the ligand and the receptor...

...Jessie Chu; P. D. Si Dong; Grace Panganiban The insect antenna and leg are considered homologous structures, likely to have arisen via duplication and divergence from an ancestral limb. Consistent with this, the antenna and leg are derived from primordia with similar developmental potentials...

...P. D. Si Dong; Jessie Chu; Grace Panganiban The morphological diversification of appendages represents a crucial aspect of animal body plan evolution. The arthropod antenna and leg are homologous appendages, thought to have arisen via duplication and divergence of an ancestral structure (Snodgrass...

... screen yielded 16 lethal point mutant alleles of dAP-2 . Null mutants die as adults or late pupae with a reduced proboscis, severely shortened legs (∼30% of normal length) lacking tarsal joints, and disruptions in the protocerebral central complex, a brain region critical for locomotion. Seven...

...Tetsuya Kojima; Makoto Sato; Kaoru Saigo ABSTRACT Here, we show that BarH1 and BarH2 , a pair of Bar homeobox genes, play essential roles in the formation and specification of the distal leg segments of Drosophila . In early third instar, juxtaposition of Bar-positive and Bar-negative tissues...

...P. D. Si Dong; Jessie Chu; Grace Panganiban ABSTRACT The Distal-less gene is known for its role in proximodistal patterning of Drosophila limbs. However, Distal-less has a second critical function during Drosophila limb development, that of distinguishing the antenna from the leg. The antenna...

... concentration. We have used a novel lineage-tagging method to address the reversibility of cell fate specification by morphogen gradients. We find that responses to Hedgehog and Dpp in the wing disc are readily reversible. In the leg, we find that cells readily adopt more distal fates, but do not normally shift...

...Jun Wu; Stephen M. Cohen The developing legs of Drosophila are subdivided into proximal and distal domains by the activity of the homeodomain proteins Homothorax (Hth) and Distal-less (Dll). The expression domains of Dll and Hth are initially reciprocal. Wingless and Dpp define both domains...

...Gerard Campbell; Andrew Tomlinson ABSTRACT In the leg and wing imaginal discs of Drosophila , the expression domains of the homeobox genes aristaless ( al ) and Distal-less ( Dll ) are defined by the secreted signaling molecules Wingless (Wg) and Decapentaplegic (Dpp). Here, the roles played by al...

... in bristles and legs of adults, as well as in mouth hooks and brains of larvae. Analysis of the mutants indicates that klumpfuss is required for proper specification and differentiation of a variety of cells, including the sensory organ mother cells and those of the distal parts of tarsal segments. We found...

...Satoshi Goto; Shigeo Hayashi ABSTRACT Two thoracic limbs of Drosophila , the leg and the wing, originate from a common cluster of cells that include the source of two secreted signaling molecules, Decapentaplegic and Wingless. We show that Wingless, but not Decapentaplegic, is responsible...

...Douglas A. Currie; Martin J. Milner; Clive W. Evans We have devised a new in vitro culture system in which cells from dissociated Drosophila leg and wing imaginal discs grow and differentiate. Primary cultures consist of epithelial and fibroblast-like cells, together with some lamellocyte-like...

...Vernon French ABSTRACT Interactions between the insect leg and surrounding thoracic epidermis were studied in the beetle, Tenebrio , by grafting the entire larval prothoracic leg into the metathoracic leg site in various orientations. Control grafts simply heal, but A/P reversed grafts lead...