In Drosophila as well as many vertebrate systems, germ cells form extraembryonically and migrate into the embryo before navigating toward gonadal mesodermal cells. How the gonadal mesoderm attracts migratory germ cells is not understood in any system. We have taken a genetic approach to identify genes required for germ cell migration in Drosophila. Here we describe the role of zfh-1 in germ cel...

Several Drosophila homeo box genes have been shown to control cell fates in specific positions or cell groups of the embryo. Because the mechanisms involved in the pattern formation of complex internal organs, such as the musculature and the nervous system, are still largely unknown, we sought to identify and analyze new homeo box genes specifically expressed in these tissues. Here, the molecul...

Freshly dissociated cells from embryonic chick neural retinas grow in characteristic patterns on flat cells or on chick embryo mesodermal cells. A striking difference between the two patterns is that the cells grown on flat cells are interconnected by a complex network of fibers, whereas those grown on mesodermal cells are aggregated into clusters that remain relatively isolated within the meso...

The cellular and developmental analysis of evolutionary-conserved genes directing bilaterian mesodermal and myogenic cell fate previously identified the hydromedusan entocodon and its differentiation product, the striated muscle, as mesodermal derivatives. In view of these findings we presented a hypothesis disputing the diploblast classification of cnidarians without providing further explanat...

Here we describe a novel Xenopus homeobox gene, milk, related by sequence homology and expression pattern to the vegetally expressed Mix.1. As is the case with Mix.1, milk is an immediate early response gene to the mesoderm inducer activin. milk is expressed at the early gastrula stage in the vegetal cells, fated to form endoderm, and in the marginal zone fated to form mesoderm. During gastrula...

We wanted to investigate the relationship between receptor tyrosine kinase (RTK) activated signaling pathways and the induction of cell migration. Using Drosophila tracheal and mesodermal cell migration as model systems, we find that the intracellular domain of the fibroblast growth factor receptors (FGFRs) Breathless (Btl) and Heartless (Htl) can be functionally replaced by the intracellular d...

Soft tissue sarcomas (STS) are tumors of mesodermal origin, comprising about 1% of all adult neoplasms. Management of such tumors is an important medical challenge. TP53 codon 72 polymorphism results in either the arginine or proline form of the p53 protein; several studies have investigated whether codon 72 polymorphisms are risk and prognostic factors for cancer. We investigated p53 codon 72 ...

The Drosophila tracheal system, a tubular network, is formed from isolated ectodermal metameres by guided branch outgrowth and branch fusion. Branch outgrowth is triggered by the localized and transient activity of Branchless (Bnl/dFGF). Here, we report the discovery of a mesodermal cell that links the leading cells of outgrowing main branches 2.5 hr before they fuse. This bridge-cell serves as...

Cats represent an unusually valuable model for studying the role of the immune response to leukemia, lymphoma, and other mesodermal neoplasms. The agents that cause spontaneous feline leukemias, lymphomas, and fibrosarcomas, the feline leukemia and sarcoma viruses, are well characterized. A specific tumor cell membrane antigen, designated the feline oncornavirus-associated cell membrane antigen...