TY - JOUR
T1 - GFAP isoforms control intermediate filament network dynamics, cell morphology, and focal adhesions
AU - Moeton, M.
AU - Stassen, O.M.J.A.
AU - Sluijs, J.A.
AU - van der Meer, V.W.N.
AU - Kluivers, L.J.
AU - van Hoorn, H.
AU - Schmidt, T.
AU - Reits, E.A.J.
AU - van Strien, M.E.
AU - Hol, E.M.
N1 - With supplementary material
PY - 2016
Y1 - 2016
N2 - Glial fibrillary acidic protein (GFAP) is the characteristic intermediate filament (IF) protein in astrocytes. Expression of its main isoforms, GFAPα and GFAPδ, varies in astrocytes and astrocytoma implying a potential regulatory role in astrocyte physiology and pathology. An IF-network is a dynamic structure and has been functionally linked to cell motility, proliferation, and morphology. There is a constant exchange of IF-proteins with the network. To study differences in the dynamic properties of GFAPα and GFAPδ, we performed fluorescence recovery after photobleaching experiments on astrocytoma cells with fluorescently tagged GFAPs. Here, we show for the first time that the exchange of GFP-GFAPδ was significantly slower than the exchange of GFP-GFAPα with the IF-network. Furthermore, a collapsed IF-network, induced by GFAPδ expression, led to a further decrease in fluorescence recovery of both GFP-GFAPα and GFP-GFAPδ. This altered IF-network also changed cell morphology and the focal adhesion size, but did not alter cell migration or proliferation. Our study provides further insight into the modulation of the dynamic properties and functional consequences of the IF-network composition.
AB - Glial fibrillary acidic protein (GFAP) is the characteristic intermediate filament (IF) protein in astrocytes. Expression of its main isoforms, GFAPα and GFAPδ, varies in astrocytes and astrocytoma implying a potential regulatory role in astrocyte physiology and pathology. An IF-network is a dynamic structure and has been functionally linked to cell motility, proliferation, and morphology. There is a constant exchange of IF-proteins with the network. To study differences in the dynamic properties of GFAPα and GFAPδ, we performed fluorescence recovery after photobleaching experiments on astrocytoma cells with fluorescently tagged GFAPs. Here, we show for the first time that the exchange of GFP-GFAPδ was significantly slower than the exchange of GFP-GFAPα with the IF-network. Furthermore, a collapsed IF-network, induced by GFAPδ expression, led to a further decrease in fluorescence recovery of both GFP-GFAPα and GFP-GFAPδ. This altered IF-network also changed cell morphology and the focal adhesion size, but did not alter cell migration or proliferation. Our study provides further insight into the modulation of the dynamic properties and functional consequences of the IF-network composition.
UR - https://pure.uva.nl/ws/files/2718356/177219_GFAP_isoforms_suppl._1.avi
UR - https://pure.uva.nl/ws/files/2718358/177220_GFAP_isoforms_suppl._2.avi
UR - https://pure.uva.nl/ws/files/2718360/177221_GFAP_isoforms_suppl._3.tif
UR - https://pure.uva.nl/ws/files/2718362/177222_GFAP_isoforms_suppl._4.jpg
UR - https://pure.uva.nl/ws/files/2718364/177223_GFAP_isoforms_suppl._5.tif
UR - https://pure.uva.nl/ws/files/2718366/177224_GFAP_isoforms_suppl._6.tif
UR - https://pure.uva.nl/ws/files/2718368/177225_GFAP_isoforms_suppl._7.jpg
UR - https://pure.uva.nl/ws/files/2718370/177226_GFAP_isoforms_suppl._8.avi
UR - https://pure.uva.nl/ws/files/2718372/177227_GFAP_isoforms_suppl._9.avi
U2 - https://doi.org/10.1007/s00018-016-2239-5
DO - https://doi.org/10.1007/s00018-016-2239-5
M3 - Article
C2 - 27141937
SN - 1420-682X
VL - 73
SP - 4101
EP - 4120
JO - Cellular and molecular life sciences
JF - Cellular and molecular life sciences
IS - 21
ER -