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Invadolysin: a novel, conserved metalloprotease links mitotic structural rearrangements with cell migration.

McHugh B, Krause SA, Yu B, Deans AM, Heasman S, McLaughlin P, Heck MM - J. Cell Biol. (2004)

Bottom Line: Zymography reveals that a protease activity, present in wild-type larval brains, is missing from homozygous tissue, and we show that IX-14/invadolysin cleaves lamin in vitro.The IX-14/invadolysin protein is predominantly found in cytoplasmic structures resembling invadopodia in fly and human cells, but is dramatically relocalized to the leading edge of migrating cells.Strikingly, we find that the directed migration of germ cells is affected in Drosophila IX-14 mutant embryos.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK.

ABSTRACT
The cell cycle is widely known to be regulated by networks of phosphorylation and ubiquitin-directed proteolysis. Here, we describe IX-14/invadolysin, a novel metalloprotease present only in metazoa, whose activity appears to be essential for mitotic progression. Mitotic neuroblasts of Drosophila melanogaster IX-14 mutant larvae exhibit increased levels of nuclear envelope proteins, monopolar and asymmetric spindles, and chromosomes that appear hypercondensed in length with a surrounding halo of loosely condensed chromatin. Zymography reveals that a protease activity, present in wild-type larval brains, is missing from homozygous tissue, and we show that IX-14/invadolysin cleaves lamin in vitro. The IX-14/invadolysin protein is predominantly found in cytoplasmic structures resembling invadopodia in fly and human cells, but is dramatically relocalized to the leading edge of migrating cells. Strikingly, we find that the directed migration of germ cells is affected in Drosophila IX-14 mutant embryos. Thus, invadolysin identifies a new family of conserved metalloproteases whose activity appears to be essential for the coordination of mitotic progression, but which also plays an unexpected role in cell migration.

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Germ cell migration defects in l(3)IX-14 embryos. All panels are dorsal views of Drosophila embryos. Left panels are phase-contrast images, middle panels show DAPI labeling of DNA, right panels show germ cells detected by Vasa antibody. (A) Wild-type Canton S embryos. (top) Stage 10/11, when germ cells are in the middle of passing through the midgut and migrating dorsally. (bottom) Stage 13, when germ cells form two elongated clusters on either side of the embryo. (B) IX-14 homozygous embryos selected for absence of the Kr-GFP balancer chromosome. (top) Stage 10/11, germ cells appear as in wild-type embryos. (bottom) Stage 13, when the abnormal germ cell migration phenotype is apparent. The germ cells fail to migrate and coalesce into gonads.
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fig9: Germ cell migration defects in l(3)IX-14 embryos. All panels are dorsal views of Drosophila embryos. Left panels are phase-contrast images, middle panels show DAPI labeling of DNA, right panels show germ cells detected by Vasa antibody. (A) Wild-type Canton S embryos. (top) Stage 10/11, when germ cells are in the middle of passing through the midgut and migrating dorsally. (bottom) Stage 13, when germ cells form two elongated clusters on either side of the embryo. (B) IX-14 homozygous embryos selected for absence of the Kr-GFP balancer chromosome. (top) Stage 10/11, germ cells appear as in wild-type embryos. (bottom) Stage 13, when the abnormal germ cell migration phenotype is apparent. The germ cells fail to migrate and coalesce into gonads.

Mentions: Given a possible role for this protein in cell migration, we examined primordial germ cell migration in wild-type and IX-14 mutant Drosophila embryos (for review see Santos and Lehmann, 2004). After being the first cells to form very early in embryogenesis, primordial germ cells are passively carried along the dorsal side of the embryo in close association with the posterior midgut primordium. As this primordium invaginates, the germ cells are carried to the interior of the embryo. After this, they actively migrate away from the midgut toward the adjacent mesoderm where they associate with somatic gonadal precursor cells. These clusters of cells further migrate and coalesce into gonads later in embryogenesis. Using Vasa as a marker for primordial germ cells, we examined embryos both before and after the migration phases. As shown in Fig. 9, germ cells in both wild-type (Fig. 9 A, top) and mutant (Fig. 9 B, top) embryos are similarly dispersed at the stage before active migration. However, a dramatic difference is seen in embryos at the later stage of gonad coalescence, with gonads visible in wild type (Fig. 9 A, bottom), but not in the mutation (Fig. 9 B, bottom). Mutant larvae then lack gonads (unpublished data). Therefore, the IX-14 protease is playing a role in cell migration, as well as in mitosis, in Drosophila.


Invadolysin: a novel, conserved metalloprotease links mitotic structural rearrangements with cell migration.

McHugh B, Krause SA, Yu B, Deans AM, Heasman S, McLaughlin P, Heck MM - J. Cell Biol. (2004)

Germ cell migration defects in l(3)IX-14 embryos. All panels are dorsal views of Drosophila embryos. Left panels are phase-contrast images, middle panels show DAPI labeling of DNA, right panels show germ cells detected by Vasa antibody. (A) Wild-type Canton S embryos. (top) Stage 10/11, when germ cells are in the middle of passing through the midgut and migrating dorsally. (bottom) Stage 13, when germ cells form two elongated clusters on either side of the embryo. (B) IX-14 homozygous embryos selected for absence of the Kr-GFP balancer chromosome. (top) Stage 10/11, germ cells appear as in wild-type embryos. (bottom) Stage 13, when the abnormal germ cell migration phenotype is apparent. The germ cells fail to migrate and coalesce into gonads.
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Related In: Results  -  Collection

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fig9: Germ cell migration defects in l(3)IX-14 embryos. All panels are dorsal views of Drosophila embryos. Left panels are phase-contrast images, middle panels show DAPI labeling of DNA, right panels show germ cells detected by Vasa antibody. (A) Wild-type Canton S embryos. (top) Stage 10/11, when germ cells are in the middle of passing through the midgut and migrating dorsally. (bottom) Stage 13, when germ cells form two elongated clusters on either side of the embryo. (B) IX-14 homozygous embryos selected for absence of the Kr-GFP balancer chromosome. (top) Stage 10/11, germ cells appear as in wild-type embryos. (bottom) Stage 13, when the abnormal germ cell migration phenotype is apparent. The germ cells fail to migrate and coalesce into gonads.
Mentions: Given a possible role for this protein in cell migration, we examined primordial germ cell migration in wild-type and IX-14 mutant Drosophila embryos (for review see Santos and Lehmann, 2004). After being the first cells to form very early in embryogenesis, primordial germ cells are passively carried along the dorsal side of the embryo in close association with the posterior midgut primordium. As this primordium invaginates, the germ cells are carried to the interior of the embryo. After this, they actively migrate away from the midgut toward the adjacent mesoderm where they associate with somatic gonadal precursor cells. These clusters of cells further migrate and coalesce into gonads later in embryogenesis. Using Vasa as a marker for primordial germ cells, we examined embryos both before and after the migration phases. As shown in Fig. 9, germ cells in both wild-type (Fig. 9 A, top) and mutant (Fig. 9 B, top) embryos are similarly dispersed at the stage before active migration. However, a dramatic difference is seen in embryos at the later stage of gonad coalescence, with gonads visible in wild type (Fig. 9 A, bottom), but not in the mutation (Fig. 9 B, bottom). Mutant larvae then lack gonads (unpublished data). Therefore, the IX-14 protease is playing a role in cell migration, as well as in mitosis, in Drosophila.

Bottom Line: Zymography reveals that a protease activity, present in wild-type larval brains, is missing from homozygous tissue, and we show that IX-14/invadolysin cleaves lamin in vitro.The IX-14/invadolysin protein is predominantly found in cytoplasmic structures resembling invadopodia in fly and human cells, but is dramatically relocalized to the leading edge of migrating cells.Strikingly, we find that the directed migration of germ cells is affected in Drosophila IX-14 mutant embryos.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK.

ABSTRACT
The cell cycle is widely known to be regulated by networks of phosphorylation and ubiquitin-directed proteolysis. Here, we describe IX-14/invadolysin, a novel metalloprotease present only in metazoa, whose activity appears to be essential for mitotic progression. Mitotic neuroblasts of Drosophila melanogaster IX-14 mutant larvae exhibit increased levels of nuclear envelope proteins, monopolar and asymmetric spindles, and chromosomes that appear hypercondensed in length with a surrounding halo of loosely condensed chromatin. Zymography reveals that a protease activity, present in wild-type larval brains, is missing from homozygous tissue, and we show that IX-14/invadolysin cleaves lamin in vitro. The IX-14/invadolysin protein is predominantly found in cytoplasmic structures resembling invadopodia in fly and human cells, but is dramatically relocalized to the leading edge of migrating cells. Strikingly, we find that the directed migration of germ cells is affected in Drosophila IX-14 mutant embryos. Thus, invadolysin identifies a new family of conserved metalloproteases whose activity appears to be essential for the coordination of mitotic progression, but which also plays an unexpected role in cell migration.

Show MeSH
Related in: MedlinePlus