TY - JOUR
T1 - In vitro formation of the "S" layer, a unique component of the fertilization envelope in Xenopus laevis eggs
AU - Larabell, Carolyn A.
AU - Chandler, Douglas E.
N1 - Funding Information:
We thank Dr. Robert Grey for helpful discussions of his unpublished data. We also thank Dr. David Bentley, University of Arizona, for the use of his IS1 DS 130 scanning electron microscope, and his assistance with the high magnification views obtained with it. This study was supported by grants from the NSF (DCB-8407152 and DCB-8810200) and the NIH (lK04-HDO0619).
PY - 1988/11
Y1 - 1988/11
N2 - The extracellular matrix (ECM) of unfertilized Xenopus laevis eggs consists of an elaborate filamentous network in the perivitelline space (PS) and a thick fibrillar vitelline envelope (VE), with a thin layer of horizontal filaments (HF) separating the two. At fertilization this ECM is converted into the fertilization envelope (comprised of the fertilization (F) layer and altered VE), and a third layer, the smooth (S) layer, is formed at the upper boundary of the PS (Larabell and Chandler, 1988). In this report, we use quick-freeze, deep-etch, rotary-shadow electron microscopy to show that an intact S layer can be formed in vitro by incubation of unfertilized eggs in an exudate obtained from cortical granules. Within 5 min numerous 36-nm-diameter particles assemble in a highly ordered array at the microvillar tips. These particles appear to "melt" and to form patches of smooth material and within 10 min one continuous sheet has formed. The presence of the VE is required for formation of the S layer, and we suggest that the HF layer is the site of assembly.
AB - The extracellular matrix (ECM) of unfertilized Xenopus laevis eggs consists of an elaborate filamentous network in the perivitelline space (PS) and a thick fibrillar vitelline envelope (VE), with a thin layer of horizontal filaments (HF) separating the two. At fertilization this ECM is converted into the fertilization envelope (comprised of the fertilization (F) layer and altered VE), and a third layer, the smooth (S) layer, is formed at the upper boundary of the PS (Larabell and Chandler, 1988). In this report, we use quick-freeze, deep-etch, rotary-shadow electron microscopy to show that an intact S layer can be formed in vitro by incubation of unfertilized eggs in an exudate obtained from cortical granules. Within 5 min numerous 36-nm-diameter particles assemble in a highly ordered array at the microvillar tips. These particles appear to "melt" and to form patches of smooth material and within 10 min one continuous sheet has formed. The presence of the VE is required for formation of the S layer, and we suggest that the HF layer is the site of assembly.
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U2 - 10.1016/0012-1606(88)90441-1
DO - 10.1016/0012-1606(88)90441-1
M3 - Article
C2 - 3181634
AN - SCOPUS:0024232180
SN - 0012-1606
VL - 130
SP - 356
EP - 364
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -