Premium
Relative Timing of Stiffening with Various Combinations of Nucleate and Enucleated Egg Fragments of Xenopus laevis
Author(s) -
Shinagawa Atsunori
Publication year - 1992
Publication title -
development, growth and differentiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.864
H-Index - 66
eISSN - 1440-169X
pISSN - 0012-1592
DOI - 10.1111/j.1440-169x.1992.00419.x
Subject(s) - xenopus , stiffening , nucleus , cytoplasm , biology , cell nucleus , biophysics , zygote , anatomy , microbiology and biotechnology , genetics , embryogenesis , embryo , materials science , gene , composite material
Previously, I found that in Xenopus eggs, the surface contraction wave (SCW) can arise at a point close to a male, a female or a zygote nucleus or a top portion of the egg (9). This finding suggested that all types of nucleus and cytoplasm of a Xenopus egg have the potential to determine the point of initiation of the SCW. Since stiffening is closely associated with the SCW, to determine the factors governing this phenomenon, I compared the times of egg stiffening of pairs of fragments containing different types of nuclei or cytoplasm. I found that the stiffening occurs earlier in fragments containing any type of nucleus than in those containing no nucleus, and earlier in fragments containing a male nucleus than in those containing a female nucleus. These results are consistent with the notion that either a nucleus or cytoplasm that induces the SCW earliest determines the point of initiation of the SCW close to itself. I also found that DNA replication is essential for the earlier occurrence of stiffening in a fragment containing a nucleus.