Among marine animals, shellfish, crustaceans, and sea urchins have total
cleavage eggs, yet almost no experimentation has been done with them. Roe are
meroblastic, and while a single organism does not appear from a single blastomere,
the separated blastomere can be used in addition with the technology described in
③ to produce a chimera.
C. Mixture and Fusion
This refers to techniques for mixing cells. Creating mixed conditions while
maintaining boundaries between different cells is relatively easy, and ordinary not
especially meaningful. Mixture of genetically different blastomeres from different
fertilized eggs early on in genesis, however, can produce a chimera.
At the same time, it is also possible to produce new hybrid cells by inducing
adhesion, membrane fusion, cytoplasm mixing, or nuclear unification between
cells. This is known as “cell fusion,” with chemicals such as polyethylene glycol or
electrical shocks typically used to induce it in cells.
D. Transplantation and Amalganation
This refers to techniques for introducing something into the cell or removing
something from it. Micropipettes may be used to extract relatively large organelles
such as nuclei and insert the nucleus from another cell (transplantation) or introduce
minute quantities of various materials into the cell (Oshiro 1990).
4.3.2 Applications
The following are some of the breeding applications of these basic techniques.
A. Gamete Selection and Improvement
Cell separation techniques may be applied to separate sperm in hetero male
animals that are believed to exist in two different varieties. Fertilization of each
allows for the production of offspring that can be distinguished between female and
male.
When sex chromosomes are of markedly different sizes, X sperm carrying X
chromosomes have a different weight (density) from Y sperm carrying Y chromosomes, and can therefore be separated by centrifuge. Taking advantage of differing charges on the sperm surface, Takashi Oshiro used a non-carrying
cataphoresis device to separate X and Y sperm in loach and obtain seedlings that
were either entirely female or entirely male. Once techniques are discovered for
dyeing two varieties of living sperm, it will be possible to separate them by cell
fractionator. Another method involves refining antigens characteristic of the sexes
to produce antibodies and separate out one sex by killing only the sperm, egg, or
embryo carrying those antigens.
4.3 Cell Manipulation
91
cleavage eggs, yet almost no experimentation has been done with them. Roe are
meroblastic, and while a single organism does not appear from a single blastomere,
the separated blastomere can be used in addition with the technology described in
③ to produce a chimera.
C. Mixture and Fusion
This refers to techniques for mixing cells. Creating mixed conditions while
maintaining boundaries between different cells is relatively easy, and ordinary not
especially meaningful. Mixture of genetically different blastomeres from different
fertilized eggs early on in genesis, however, can produce a chimera.
At the same time, it is also possible to produce new hybrid cells by inducing
adhesion, membrane fusion, cytoplasm mixing, or nuclear unification between
cells. This is known as “cell fusion,” with chemicals such as polyethylene glycol or
electrical shocks typically used to induce it in cells.
D. Transplantation and Amalganation
This refers to techniques for introducing something into the cell or removing
something from it. Micropipettes may be used to extract relatively large organelles
such as nuclei and insert the nucleus from another cell (transplantation) or introduce
minute quantities of various materials into the cell (Oshiro 1990).
4.3.2 Applications
The following are some of the breeding applications of these basic techniques.
A. Gamete Selection and Improvement
Cell separation techniques may be applied to separate sperm in hetero male
animals that are believed to exist in two different varieties. Fertilization of each
allows for the production of offspring that can be distinguished between female and
male.
When sex chromosomes are of markedly different sizes, X sperm carrying X
chromosomes have a different weight (density) from Y sperm carrying Y chromosomes, and can therefore be separated by centrifuge. Taking advantage of differing charges on the sperm surface, Takashi Oshiro used a non-carrying
cataphoresis device to separate X and Y sperm in loach and obtain seedlings that
were either entirely female or entirely male. Once techniques are discovered for
dyeing two varieties of living sperm, it will be possible to separate them by cell
fractionator. Another method involves refining antigens characteristic of the sexes
to produce antibodies and separate out one sex by killing only the sperm, egg, or
embryo carrying those antigens.
4.3 Cell Manipulation
91