DrosophilaE-cadherin is essential for proper germ cell-soma interaction during gonad morphogenesis

Abstract

In most animal species, germ cells require intimate contact with specialized somatic cells in the gonad for their proper development. We have analyzed the establishment of germ cell-soma interaction during embryonic gonad formation in Drosophila melanogaster, and find that somatic cells undergo dramatic changes in cell shape and individually ensheath germ cells as the gonad coalesces. Germ cell ensheathment is independent of other aspects of gonad formation, indicating that separate morphogenic processes are at work during gonadogenesis. The cell-cell adhesion molecule Drosophila E-cadherin is essential both for germ cell ensheathment and gonad compaction, and is upregulated in the somatic gonad at the time of gonad formation. Our data indicate that differential cell adhesion contributes to cell sorting and the formation of proper gonad architecture. In addition, we find that Fear of Intimacy, a novel transmembrane protein, is also required for both germ cell ensheathment and gonad compaction. Ecadherin expression in the gonad is dramatically decreased in fear of intimacy mutants, indicating that Fear of Intimacy may be a regulator of E-cadherin expression or function.

Transition from non-motile behaviour to directed migration during early PGC development in zebrafish

“…Although E-cadherin is down regulated on the membrane of PGCs upon onset of migration, its expression persists in the cells as they migrate. This finding is consistent with the idea that similar to PGCs and other cell types in different organisms (Bendel-Stenzel et al, 1998;Dumstrei et al, 2002;Jenkins et al, 2003;Montero and Heisenberg, 2004;Niewiadomska et al, 1999), zebrafish germ cells probably require a certain level of E-cadherin for their proper migration and cell morphology. To test this notion more directly, we have forced expressed E-cadherin in the PGCs and monitored their behaviour.…”

Drosophila fear of intimacy Encodes a Zrt/IRT-like Protein (ZIP) Family Zinc Transporter Functionally Related to Mammalian ZIP Proteins

“…foi mutant embryos have defects in gonad coalescence, in which the cells of the gonad fail to properly associate with one another, and in trachea formation, in which some tracheal branches fail to connect correctly with neighboring branches (2,42). Expression of each HA-tagged version of FOI in the appropriate tissue was able to fully rescue the gonad and tracheal defects normally observed in foi mutants (Fig.…”

“…These proteins may act, at least in part, by affecting the expression or function of the calcium-dependent cell adhesion molecule E-cadherin. Like FOI, E-cadherin is required in Drosophila for both gonad and trachea morphogenesis (2,49), and expression of E-cadherin is strongly reduced in foi mutants (42). Thus, FOI may affect morphogenesis primarily by affecting E-cadherin.…”

Somatic gonadal cells: The supporting cast for the germline

“…Beginning at stage 13, the SGPs send out extensions to surround the PGCs in a process called ensheathment ( Fig. 1; Jenkins et al, 2003). The ensheathment of germ cells by somatic cells persists throughout development (Decotto and Spradling, 2005;Gonczy and DiNardo, 1996;Jenkins et al, 2003).…”

“…1; Jenkins et al, 2003). The ensheathment of germ cells by somatic cells persists throughout development (Decotto and Spradling, 2005;Gonczy and DiNardo, 1996;Jenkins et al, 2003). At stage 14, msSGPs coalesce with the rest of the gonad (DeFalco et al, 2003).…”