Peripheral astrocyte processes: Monitoring by selective immunostaining for the actin‐binding ERM proteins

GLIA - Tập 36 Số 3 - Trang 330-341 - 2001
Amin Derouiche1,2, Michael Frotscher3
1Institute of Anatomy, University of Dresden, Dresden, Germany
2Max-Planck Institute for Brain Research, Frankfurt am Main, Germany
3Institute of Anatomy, University of Freiburg, Freiburg, Germany

Tóm tắt

AbstractAstrocytes extend thin lamellate processes in the neuropil, in particular around synapses, where they can modulate synaptic function or mediate glial–neuronal communication. Previous studies have shown that these lamellate perisynaptic processes change their shape in response to neuronal activity, but the underlying mechanisms have remained unclear. Similarly, the molecular composition of these fine, sheet‐like astrocytic processes (often 50–100 nm wide) is not understood but has to be related to their dynamic properties. To this end, we have studied the presence of ezrin, radixin, and moesin (ERM proteins) in the rat hippocampus and in primary cultured astrocytes, applying immunoperoxidase, immunofluorescence, and immunogold techniques. These three ERM proteins are known as actin‐binding proteins that link the cell membrane to the actin cytoskeleton, particularly in microvillus‐bearing epithelial cells. In cell culture, anti‐ezrin and antiradixin, but not antimoesin, antibodies were specific for astrocytes, which often displayed selective staining of filopodia and microvilli. Nonoverlapping visualization of astrocytic peripheral and stem processes was obtained by immunocytochemical double labeling for ezrin and GFAP, respectively. In sections of rat hippocampus, homogeneous labeling of the neuropil, but not of cell layers, resulted from immunostaining of fine, peripheral astrocyte processes, as confirmed ultrastructurally. Our data show that the fine peripheral processes of astrocytes, which also constitute the perisynaptic glial sheath, are specialized in that they contain characteristic actin‐associated molecules, likely to contribute to their dynamic properties. Applying anti‐ezrin and anti‐radixin as selective markers, plasticity of these perisynaptic glial processes can be analyzed. GLIA 36:330–341, 2001. © 2001 Wiley‐Liss, Inc.

Từ khóa


Tài liệu tham khảo

10.1016/S0166-2236(98)01349-6

Berryman M, 1993, Erzin is concentrated in the apical microvilli of a wide variety of epithelial cells whereas moesin is found primarily in endothelial cells, J Cell Sci, 105, 1025, 10.1242/jcs.105.4.1025

10.1002/jnr.490300124

Böhling T, 1996, Ezrin expression in stromal cells of capillary hemangioblastoma—an immunohistochemical survey of brain tumors, Am J Pathol, 148, 367

10.1073/pnas.85.23.9336

10.1083/jcb.97.2.425

10.1083/jcb.108.3.921

10.1016/S0079-6123(00)25011-5

10.1002/1098-1063(2000)10:5<569::AID-HIPO7>3.0.CO;2-M

10.1007/978-3-642-60704-2_20

10.1016/0006-8993(91)90103-3

10.1002/jnr.490420115

10.1038/19978

10.1177/38.8.2114439

10.1007/BF01175194

10.1083/jcb.115.4.1039

10.1007/BF00492479

10.1002/glia.440100108

10.1016/S0002-9440(10)64816-X

Geiger K, 2000, The actin‐binding protein ezrin as a marker of astrocyte activation. Neuropathology 2000. Birmingham, UK, 2–6.9.2000, Brain Pathol, 10, 708

10.1097/00005072-199111000-00009

10.1083/jcb.109.4.1621

10.1016/S0006-8993(96)01249-8

10.1038/5692

10.1038/382265a0

10.1096/fasebj.9.5.7534736

Hansson E, 1994, Metabotropic glutamate receptor activation induces astroglial swelling, J Biol Chem, 269, 21955, 10.1016/S0021-9258(17)31741-6

10.1083/jcb.135.1.37

10.1007/BF00268017

Hsu SMR, 1981, The use of avidin biotin complex (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled antibody (peroxidase) procedures, J Histochem, 29, 577

10.1038/3684

10.1038/360467a0

10.1016/0306-4522(86)90112-0

10.1016/S0960-9822(06)00295-8

10.1046/j.1460-9568.2000.00264.x

10.1016/0896-6273(88)90103-1

10.1016/S0962-8924(99)01544-5

10.1083/jcb.85.3.890

10.1083/jcb.139.1.193

10.1097/00005072-199405000-00001

10.1016/0006-8993(79)90071-4

10.1126/science.1059162

10.1083/jcb.143.2.443

10.1002/cne.903260107

10.1016/0896-6273(94)90038-8

Rueger DC, 1981, Purified glial fibrillary acidic protein and desmin are distinct intermediate filament proteins exhibiting similar properties, J Biol Chem, 256, 10606, 10.1016/S0021-9258(19)68666-7

10.1523/JNEUROSCI.18-09-03158.1998

10.1083/jcb.113.2.321

10.1182/blood.V91.12.4632

Shayakul C, 1997, Localization of the high‐affinity glutamate transporter EAAC1 in rat kidney, Am J Physiol, 273, F1023

10.1007/BF00341419

10.1046/j.1460-9568.1999.00460.x

10.1083/jcb.125.6.1371

10.1016/0306-4522(93)90002-W

10.1083/jcb.108.6.2369

10.1083/jcb.126.2.391

10.1016/S0968-0004(96)10071-2

10.1016/S0955-0674(97)80154-8

10.1083/jcb.126.6.1445

10.1016/S0042-6989(96)00134-4

WickW GrimmelC Wild‐BodeC PlattenM ArpinM WellerM.2001.Ezrin‐dependent promotion of glioma cell clonogenicity motility and invasion mediated by BCL‐2 and transforming growth factor‐beta2. J Neurosci.21:3360–3368.

WolffJR.1970.Quantitative aspects of astroglia. In: Proceedings of the sixth international congress of neuropathology. Paris: Masson; p327–352.

10.1074/jbc.271.12.7224

10.1083/jcb.140.4.885