THE TRANSPLANTATION OF LIVING CELL NUCLEI
J. B. GURDON
Department of Zoology y Oxford University, England
I. Introduction
1
II. Techniques of Nuclear Transplantation
2
A. Transfer of Nuclei with Cytoplasm
2
B. Transfer of Isolated Nuclei
10
C. Summary
12
III. Results of Nuclear Transfer Experiments
14
A. Stable Changes in Living Nuclei
14
B. Reversible Changes in Living Nuclei
25
C. Nuclear or Cytoplasmic Control of Differentiation
28
D. Intracellular Communication
31
IV. Conclusions from Nuclear Transfer Experiments Compared with those from
other Experiments
33
A. Variation in the Genetic Material of Differentiating Cells
33
B. Stable Activation or Repression of Genetic Material
34
C. Reversible Gene Activation and Repression
37
V. Summary and Prospects
40
References
41
I. Introduction
The problem of cell differentiation can at present be considered to
have two main aspects: the first of these is the regulation of information
transfer, a process determining what kind of molecules are synthesized
in the cell; the second is the spatial arrangement of these molecules into
cell structures, or the genesis of shape. The transplantation of living
nuclei is a kind of experiment which has so far contributed mainly to
the former aspect of differentiation, especially to the control of gene
activity and to the stability of gene expression. It is therefore indirectly
relevant to morphogenesis.
This review contains three main sections. The first describes the techniques that have been developed for transplanting nuclei in different
organisms. The intention is to discuss the achievements and limitations
of these techniques and hence the kind of problems to which each can
most usefully be applied.
In the next section (III) the results of the different kinds of nuclear
transfer experiments are summarized and are arranged according to
the type of conclusion that can be drawn from them.
A2
1
J. B. GURDON
Department of Zoology y Oxford University, England
I. Introduction
1
II. Techniques of Nuclear Transplantation
2
A. Transfer of Nuclei with Cytoplasm
2
B. Transfer of Isolated Nuclei
10
C. Summary
12
III. Results of Nuclear Transfer Experiments
14
A. Stable Changes in Living Nuclei
14
B. Reversible Changes in Living Nuclei
25
C. Nuclear or Cytoplasmic Control of Differentiation
28
D. Intracellular Communication
31
IV. Conclusions from Nuclear Transfer Experiments Compared with those from
other Experiments
33
A. Variation in the Genetic Material of Differentiating Cells
33
B. Stable Activation or Repression of Genetic Material
34
C. Reversible Gene Activation and Repression
37
V. Summary and Prospects
40
References
41
I. Introduction
The problem of cell differentiation can at present be considered to
have two main aspects: the first of these is the regulation of information
transfer, a process determining what kind of molecules are synthesized
in the cell; the second is the spatial arrangement of these molecules into
cell structures, or the genesis of shape. The transplantation of living
nuclei is a kind of experiment which has so far contributed mainly to
the former aspect of differentiation, especially to the control of gene
activity and to the stability of gene expression. It is therefore indirectly
relevant to morphogenesis.
This review contains three main sections. The first describes the techniques that have been developed for transplanting nuclei in different
organisms. The intention is to discuss the achievements and limitations
of these techniques and hence the kind of problems to which each can
most usefully be applied.
In the next section (III) the results of the different kinds of nuclear
transfer experiments are summarized and are arranged according to
the type of conclusion that can be drawn from them.
A2
1