Limits...
Ectodomain shedding of L1 adhesion molecule promotes cell migration by autocrine binding to integrins.

Mechtersheimer S, Gutwein P, Agmon-Levin N, Stoeck A, Oleszewski M, Riedle S, Postina R, Fahrenholz F, Fogel M, Lemmon V, Altevogt P - J. Cell Biol. (2001)

Bottom Line: The induction of migration was blocked by alpha v beta 5-specific antibodies and required Arg-Gly-Asp sites in L1.We propose that ectodomain-released L1 promotes migration by autocrine/paracrine stimulation via alpha v beta 5.This regulatory loop could be relevant for migratory processes under physiological and pathophysiological conditions.

View Article: PubMed Central - PubMed

Affiliation: Tumor Immunology Program, G0100, German Cancer Research Center, D-69120 Heidelberg, Germany.

ABSTRACT
The L1 adhesion molecule plays an important role in axon guidance and cell migration in the nervous system. L1 is also expressed by many human carcinomas. In addition to cell surface expression, the L1 ectodomain can be released by a metalloproteinase, but the biological function of this process is unknown. Here we demonstrate that membrane-proximal cleavage of L1 can be detected in tumors and in the developing mouse brain. The shedding of L1 involved a disintegrin and metalloproteinase (ADAM)10, as transfection with dominant-negative ADAM10 completely abolishes L1 release. L1-transfected CHO cells (L1-CHO) showed enhanced haptotactic migration on fibronectin and laminin, which was blocked by antibodies to alpha v beta 5 and L1. Migration of L1-CHO cells, but not the basal migration of CHO cells, was blocked by a metalloproteinase inhibitor, indicating a role for L1 shedding in the migration process. CHO and metalloproteinase-inhibited L1-CHO cells were stimulated to migrate by soluble L1-Fc protein. The induction of migration was blocked by alpha v beta 5-specific antibodies and required Arg-Gly-Asp sites in L1. A 150-kD L1 fragment released by plasmin could also stimulate CHO cell migration. We propose that ectodomain-released L1 promotes migration by autocrine/paracrine stimulation via alpha v beta 5. This regulatory loop could be relevant for migratory processes under physiological and pathophysiological conditions.

Show MeSH

Related in: MedlinePlus

The level of L1 expression affects cell migration. SKOV3 cell variants differing in the expression levels of L1 (SKOV3hi or SKOV3lo) were established by repeated FACS sorting. (A) Cytofluorographic staining of SKOV3hi or SKOV3lo cells with mAb UJ 127.11. (B) Analysis of cell adhesion and haptotactic cell migration of SKOV3hi or SKOV3lo cells. The assays were done as described in Figs. 5 E and 7 C, respectively. (C) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on FN was tested as described in Fig. 6 A. (D) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on laminin was tested as described in Fig. 6 A.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2198870&req=5

fig8: The level of L1 expression affects cell migration. SKOV3 cell variants differing in the expression levels of L1 (SKOV3hi or SKOV3lo) were established by repeated FACS sorting. (A) Cytofluorographic staining of SKOV3hi or SKOV3lo cells with mAb UJ 127.11. (B) Analysis of cell adhesion and haptotactic cell migration of SKOV3hi or SKOV3lo cells. The assays were done as described in Figs. 5 E and 7 C, respectively. (C) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on FN was tested as described in Fig. 6 A. (D) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on laminin was tested as described in Fig. 6 A.

Mentions: We examined whether the expression level of L1 could influence the rate of cell migration. SKOV3 cells were subjected to several rounds of cell sorting and stable cell populations with elevated or reduced expression of L1 were established. As shown in Fig. 8 A, SKOV3hi expressed approximately threefold higher levels of L1 as compared with SKOV3lo cells (mean fluorescence 24–58). As established by ELISA, SKOV3hi, and SKOV3lo cells also released different amounts of soluble L1 into the medium (unpublished data).


Ectodomain shedding of L1 adhesion molecule promotes cell migration by autocrine binding to integrins.

Mechtersheimer S, Gutwein P, Agmon-Levin N, Stoeck A, Oleszewski M, Riedle S, Postina R, Fahrenholz F, Fogel M, Lemmon V, Altevogt P - J. Cell Biol. (2001)

The level of L1 expression affects cell migration. SKOV3 cell variants differing in the expression levels of L1 (SKOV3hi or SKOV3lo) were established by repeated FACS sorting. (A) Cytofluorographic staining of SKOV3hi or SKOV3lo cells with mAb UJ 127.11. (B) Analysis of cell adhesion and haptotactic cell migration of SKOV3hi or SKOV3lo cells. The assays were done as described in Figs. 5 E and 7 C, respectively. (C) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on FN was tested as described in Fig. 6 A. (D) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on laminin was tested as described in Fig. 6 A.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2198870&req=5

fig8: The level of L1 expression affects cell migration. SKOV3 cell variants differing in the expression levels of L1 (SKOV3hi or SKOV3lo) were established by repeated FACS sorting. (A) Cytofluorographic staining of SKOV3hi or SKOV3lo cells with mAb UJ 127.11. (B) Analysis of cell adhesion and haptotactic cell migration of SKOV3hi or SKOV3lo cells. The assays were done as described in Figs. 5 E and 7 C, respectively. (C) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on FN was tested as described in Fig. 6 A. (D) Cells were preincubated with the indicated mAbs at 10 mg/ml and transmigration on laminin was tested as described in Fig. 6 A.
Mentions: We examined whether the expression level of L1 could influence the rate of cell migration. SKOV3 cells were subjected to several rounds of cell sorting and stable cell populations with elevated or reduced expression of L1 were established. As shown in Fig. 8 A, SKOV3hi expressed approximately threefold higher levels of L1 as compared with SKOV3lo cells (mean fluorescence 24–58). As established by ELISA, SKOV3hi, and SKOV3lo cells also released different amounts of soluble L1 into the medium (unpublished data).

Bottom Line: The induction of migration was blocked by alpha v beta 5-specific antibodies and required Arg-Gly-Asp sites in L1.We propose that ectodomain-released L1 promotes migration by autocrine/paracrine stimulation via alpha v beta 5.This regulatory loop could be relevant for migratory processes under physiological and pathophysiological conditions.

View Article: PubMed Central - PubMed

Affiliation: Tumor Immunology Program, G0100, German Cancer Research Center, D-69120 Heidelberg, Germany.

ABSTRACT
The L1 adhesion molecule plays an important role in axon guidance and cell migration in the nervous system. L1 is also expressed by many human carcinomas. In addition to cell surface expression, the L1 ectodomain can be released by a metalloproteinase, but the biological function of this process is unknown. Here we demonstrate that membrane-proximal cleavage of L1 can be detected in tumors and in the developing mouse brain. The shedding of L1 involved a disintegrin and metalloproteinase (ADAM)10, as transfection with dominant-negative ADAM10 completely abolishes L1 release. L1-transfected CHO cells (L1-CHO) showed enhanced haptotactic migration on fibronectin and laminin, which was blocked by antibodies to alpha v beta 5 and L1. Migration of L1-CHO cells, but not the basal migration of CHO cells, was blocked by a metalloproteinase inhibitor, indicating a role for L1 shedding in the migration process. CHO and metalloproteinase-inhibited L1-CHO cells were stimulated to migrate by soluble L1-Fc protein. The induction of migration was blocked by alpha v beta 5-specific antibodies and required Arg-Gly-Asp sites in L1. A 150-kD L1 fragment released by plasmin could also stimulate CHO cell migration. We propose that ectodomain-released L1 promotes migration by autocrine/paracrine stimulation via alpha v beta 5. This regulatory loop could be relevant for migratory processes under physiological and pathophysiological conditions.

Show MeSH
Related in: MedlinePlus