TY - JOUR
T1 - Transmission electron microscope studies of the nuclear envelope in Caenorhabditis elegans embryos
AU - Cohen, Merav
AU - Tzur, Yonatan B.
AU - Neufeld, Esther
AU - Feinstein, Naomi
AU - Delannoy, Michael R.
AU - Wilson, Katherine L.
AU - Gruenbaum, Yosef
N1 - Funding Information:
We are grateful to Ueli Aebi and Terry Allen for stimulating discussions and for providing dimensions for the NPC (Ueli Aebi and Terry Allen) and perinuclear space (Ueli Aebi). This work was supported by grants from the USA–Israel Binational Science Foundation (BSF), the Israel Science Foundation (ISF), the German–Israel Foundation (GIF 1-573-036.13), and the Austrian Bank (to Y.G.), the National Institutes of Health (GM64535 to K.L.W.), and the Journal of Cell Science for a travel allowance (M.C.).
PY - 2002
Y1 - 2002
N2 - Nuclear membranes and nuclear pore complexes (NPCs) are conserved in both animals and plants. However, the lamina composition and the dimensions of NPCs vary between plants, yeast, and vertebrates. In this study, we established a protocol that preserves the structure of Caenorhabditis elegans embryonic cells for high-resolution studies with thin-section transmission electron microscopy (TEM). We show that the NPCs are bigger in C. elegans embryos than in yeast, with dimensions similar to those in higher eukaryotes. We also localized the C. elegans nuclear envelope proteins Ce-lamin and Ce-emerin by pre-embedding gold labeling immunoelectron microscopy. Both proteins are present at or near the inner nuclear membrane. A fraction of Ce-lamin, but not Ce-emerin, is present in the nuclear interior. Removing the nuclear membranes leaves both Ce-lamin and Ce-emerin associated with the chromatin. Eliminating the single lamin protein caused cell death as visualized by characteristic changes in nuclear architecture including condensation of chromatin, clustering of NPCs, membrane blebbing, and the presence of vesicles inside the nucleus. Taken together, these results show evolutionarily conserved protein localization, interactions, and functions of the C. elegans nuclear envelope.
AB - Nuclear membranes and nuclear pore complexes (NPCs) are conserved in both animals and plants. However, the lamina composition and the dimensions of NPCs vary between plants, yeast, and vertebrates. In this study, we established a protocol that preserves the structure of Caenorhabditis elegans embryonic cells for high-resolution studies with thin-section transmission electron microscopy (TEM). We show that the NPCs are bigger in C. elegans embryos than in yeast, with dimensions similar to those in higher eukaryotes. We also localized the C. elegans nuclear envelope proteins Ce-lamin and Ce-emerin by pre-embedding gold labeling immunoelectron microscopy. Both proteins are present at or near the inner nuclear membrane. A fraction of Ce-lamin, but not Ce-emerin, is present in the nuclear interior. Removing the nuclear membranes leaves both Ce-lamin and Ce-emerin associated with the chromatin. Eliminating the single lamin protein caused cell death as visualized by characteristic changes in nuclear architecture including condensation of chromatin, clustering of NPCs, membrane blebbing, and the presence of vesicles inside the nucleus. Taken together, these results show evolutionarily conserved protein localization, interactions, and functions of the C. elegans nuclear envelope.
KW - Electron microscopy
KW - Lamin
KW - Nuclear envelope
KW - Nuclear lamina
KW - Nuclear pore complexes
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U2 - 10.1016/S1047-8477(02)00516-6
DO - 10.1016/S1047-8477(02)00516-6
M3 - Article
C2 - 12490171
AN - SCOPUS:0036968817
SN - 1047-8477
VL - 140
SP - 232
EP - 240
JO - Journal of Structural Biology
JF - Journal of Structural Biology
IS - 1-3
ER -