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Regulatory mechanisms required for DE-cadherin function in cell migration and other types of adhesion.

Pacquelet A, Rørth P - J. Cell Biol. (2005)

Bottom Line: We have investigated the requirements for Drosophila melanogaster epithelial (DE) cadherin regulation in vivo.We found that (1) although linking DE-cadherin to alpha-catenin is essential, regulation of the link is not required in any of these types of adhesion; (2) beta-catenin is required only to link DE-cadherin to alpha-catenin; and (3) the cytoplasmic domain of DE-cadherin has an additional specific function for the invasive migration of border cells, which is conserved to other cadherins.The nature of this additional function is discussed.

View Article: PubMed Central - PubMed

Affiliation: European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany.

ABSTRACT
Cadherin-mediated adhesion can be regulated at many levels, as demonstrated by detailed analysis in cell lines. We have investigated the requirements for Drosophila melanogaster epithelial (DE) cadherin regulation in vivo. Investigating D. melanogaster oogenesis as a model system allowed the dissection of DE-cadherin function in several types of adhesion: cell sorting, cell positioning, epithelial integrity, and the cadherin-dependent process of border cell migration. We generated multiple fusions between DE-cadherin and alpha-catenin as well as point-mutated beta-catenin and analyzed their ability to support these types of adhesion. We found that (1) although linking DE-cadherin to alpha-catenin is essential, regulation of the link is not required in any of these types of adhesion; (2) beta-catenin is required only to link DE-cadherin to alpha-catenin; and (3) the cytoplasmic domain of DE-cadherin has an additional specific function for the invasive migration of border cells, which is conserved to other cadherins. The nature of this additional function is discussed.

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Role of the cytoplasmic tail of DE-cadherin. (A) Schematic representation of DE-cadherin-FL/α-catenin and DE-cadherinΔCyt/CD2/α-catenin. (B–H) Expression of DE-cadherin-FL/α-catenin (B–E) and DE-cadherinΔCyt/CD2/α-catenin (F–H) in shg mutant follicle (B, C, F, and G) and border cells (H) or in arm mutant follicle cells (D and E). (B–G) Mutant cells are to the right of and/or below the green line. (H) Five border cells (asterisks) are shg mutant and express UAS–DE-cadherinΔCyt/CD2/α-catenin. (B, D, F, and H) All DE-cadherin is detected. (C, E, and G) Only surface DE-cadherin is detected. (H) Phalloidin (red) stains F-actin and DE-cadherin is in blue. (I) Border cell migration in shg- or arm- mutant border cell clones expressing the indicated transgenes. Bars (F), 20 μm; (H and H′) 10 μm.
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fig4: Role of the cytoplasmic tail of DE-cadherin. (A) Schematic representation of DE-cadherin-FL/α-catenin and DE-cadherinΔCyt/CD2/α-catenin. (B–H) Expression of DE-cadherin-FL/α-catenin (B–E) and DE-cadherinΔCyt/CD2/α-catenin (F–H) in shg mutant follicle (B, C, F, and G) and border cells (H) or in arm mutant follicle cells (D and E). (B–G) Mutant cells are to the right of and/or below the green line. (H) Five border cells (asterisks) are shg mutant and express UAS–DE-cadherinΔCyt/CD2/α-catenin. (B, D, F, and H) All DE-cadherin is detected. (C, E, and G) Only surface DE-cadherin is detected. (H) Phalloidin (red) stains F-actin and DE-cadherin is in blue. (I) Border cell migration in shg- or arm- mutant border cell clones expressing the indicated transgenes. Bars (F), 20 μm; (H and H′) 10 μm.

Mentions: The inability of DE-cadherinΔCyt/α-catenin to support border cell migration could be a result of the covalent fusion of α-catenin to DE-cadherin, which would indicate that a regulation of the link between DE-cadherin and α-catenin is required for border cell migration. Alternatively, the absence of rescue could be a result of the lack of a sequence in DE-cadherin cytoplasmic domain that is required for DE-cadherin function in border cells. To distinguish between these two possibilities, FL DE-cadherin/α-catenin was generated in which the FL cytoplasmic domain of DE-cadherin was retained and α-catenin fused at the COOH terminus (Fig. 4 A). Similarly to DE-cadherinΔCyt/α-catenin, DE-cadherin-FL/α-catenin prevents any regulation of the link between DE-cadherin and α-catenin but still carries all the information that may be contained in the DE-cadherin cytoplasmic domain. DE-cadherin-FL/α-catenin was expressed efficiently in shg mutant follicle cells (Fig. 4 B), accumulated at the plasma membrane (Fig. 4 C), and, to some extent, accumulated inside the cells. DE-cadherin-FL/α-catenin rescued shg phenotypes such as follicle cell sorting (Fig. 4 B), loss of epithelial integrity (Fig. 4 B), and oocyte mispositioning (Fig. S3 A, available at http://www.jcb.org/cgi/content/full/jcb.200506131/DC1). DE-cadherin-FL/α-catenin also fully rescued the migration defects of shg mutant border cells (Fig. 4 G).


Regulatory mechanisms required for DE-cadherin function in cell migration and other types of adhesion.

Pacquelet A, Rørth P - J. Cell Biol. (2005)

Role of the cytoplasmic tail of DE-cadherin. (A) Schematic representation of DE-cadherin-FL/α-catenin and DE-cadherinΔCyt/CD2/α-catenin. (B–H) Expression of DE-cadherin-FL/α-catenin (B–E) and DE-cadherinΔCyt/CD2/α-catenin (F–H) in shg mutant follicle (B, C, F, and G) and border cells (H) or in arm mutant follicle cells (D and E). (B–G) Mutant cells are to the right of and/or below the green line. (H) Five border cells (asterisks) are shg mutant and express UAS–DE-cadherinΔCyt/CD2/α-catenin. (B, D, F, and H) All DE-cadherin is detected. (C, E, and G) Only surface DE-cadherin is detected. (H) Phalloidin (red) stains F-actin and DE-cadherin is in blue. (I) Border cell migration in shg- or arm- mutant border cell clones expressing the indicated transgenes. Bars (F), 20 μm; (H and H′) 10 μm.
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Related In: Results  -  Collection

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fig4: Role of the cytoplasmic tail of DE-cadherin. (A) Schematic representation of DE-cadherin-FL/α-catenin and DE-cadherinΔCyt/CD2/α-catenin. (B–H) Expression of DE-cadherin-FL/α-catenin (B–E) and DE-cadherinΔCyt/CD2/α-catenin (F–H) in shg mutant follicle (B, C, F, and G) and border cells (H) or in arm mutant follicle cells (D and E). (B–G) Mutant cells are to the right of and/or below the green line. (H) Five border cells (asterisks) are shg mutant and express UAS–DE-cadherinΔCyt/CD2/α-catenin. (B, D, F, and H) All DE-cadherin is detected. (C, E, and G) Only surface DE-cadherin is detected. (H) Phalloidin (red) stains F-actin and DE-cadherin is in blue. (I) Border cell migration in shg- or arm- mutant border cell clones expressing the indicated transgenes. Bars (F), 20 μm; (H and H′) 10 μm.
Mentions: The inability of DE-cadherinΔCyt/α-catenin to support border cell migration could be a result of the covalent fusion of α-catenin to DE-cadherin, which would indicate that a regulation of the link between DE-cadherin and α-catenin is required for border cell migration. Alternatively, the absence of rescue could be a result of the lack of a sequence in DE-cadherin cytoplasmic domain that is required for DE-cadherin function in border cells. To distinguish between these two possibilities, FL DE-cadherin/α-catenin was generated in which the FL cytoplasmic domain of DE-cadherin was retained and α-catenin fused at the COOH terminus (Fig. 4 A). Similarly to DE-cadherinΔCyt/α-catenin, DE-cadherin-FL/α-catenin prevents any regulation of the link between DE-cadherin and α-catenin but still carries all the information that may be contained in the DE-cadherin cytoplasmic domain. DE-cadherin-FL/α-catenin was expressed efficiently in shg mutant follicle cells (Fig. 4 B), accumulated at the plasma membrane (Fig. 4 C), and, to some extent, accumulated inside the cells. DE-cadherin-FL/α-catenin rescued shg phenotypes such as follicle cell sorting (Fig. 4 B), loss of epithelial integrity (Fig. 4 B), and oocyte mispositioning (Fig. S3 A, available at http://www.jcb.org/cgi/content/full/jcb.200506131/DC1). DE-cadherin-FL/α-catenin also fully rescued the migration defects of shg mutant border cells (Fig. 4 G).

Bottom Line: We have investigated the requirements for Drosophila melanogaster epithelial (DE) cadherin regulation in vivo.We found that (1) although linking DE-cadherin to alpha-catenin is essential, regulation of the link is not required in any of these types of adhesion; (2) beta-catenin is required only to link DE-cadherin to alpha-catenin; and (3) the cytoplasmic domain of DE-cadherin has an additional specific function for the invasive migration of border cells, which is conserved to other cadherins.The nature of this additional function is discussed.

View Article: PubMed Central - PubMed

Affiliation: European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany.

ABSTRACT
Cadherin-mediated adhesion can be regulated at many levels, as demonstrated by detailed analysis in cell lines. We have investigated the requirements for Drosophila melanogaster epithelial (DE) cadherin regulation in vivo. Investigating D. melanogaster oogenesis as a model system allowed the dissection of DE-cadherin function in several types of adhesion: cell sorting, cell positioning, epithelial integrity, and the cadherin-dependent process of border cell migration. We generated multiple fusions between DE-cadherin and alpha-catenin as well as point-mutated beta-catenin and analyzed their ability to support these types of adhesion. We found that (1) although linking DE-cadherin to alpha-catenin is essential, regulation of the link is not required in any of these types of adhesion; (2) beta-catenin is required only to link DE-cadherin to alpha-catenin; and (3) the cytoplasmic domain of DE-cadherin has an additional specific function for the invasive migration of border cells, which is conserved to other cadherins. The nature of this additional function is discussed.

Show MeSH
Related in: MedlinePlus