THE ROLE OF NUCLEIC ACIDS AND SULPHYDRYL GROUPS
IN MORPHOGENESIS (AMPHIBIAN
EGG DEVELOPMENT.
REGENERATION IN
ACETABULARIA)
JEAN BRÄCHET
Faculté des Sciences, Université libre de Bruxelles, Belgium
I. Introduction
247
II. DNA in Amphibian Eggs and Acetabularia
249
A. Amphibian Egg Development
249
B. Acetabularia
256
III. RNA Distribution and Synthesis in Amphibian Eggs and Acetabularia
259
A. Amphibian Egg Development
259
Β. Acetabularia
268
IV. Sulphydryl Groups and Morphogenesis
274
A. Introductory Remarks
274
B. The Effects of j3-Mercaptoethanol on Morphogenesis
275
C. The Effects of α-Lipoic Acid on Morphogenesis (Amphibian Eggs and
Acetabularia)
283
D. Biochemical Effects of j3-Mercaptoethanol on Developing Organisms
286
V. Discussion
290
References
297
I. Introduction
It is the aim of chemical embryology to explain the intricate processes
of differentiation in terms of the synthesis and properties of the molecules
which build up the embryo: chemical embryologists have been
'molecular biologists', but without knowing it, long before molecular
biology became fashionable.f
Under the powerful impact of biochemical genetics, molecular biology
has been mainly concerned with the nature and transfer of genetic
information. It is now generally admitted that the genetic material is
deoxyribonucleic acid (DNA), which ultimately controls the synthesis of
specific proteins, enzymes or haemoglobin for instance. This control is,
however, indirect, and intermediates must exist between DNA and the
protein which is being built : these intermediates are the ribonucleic acids
(RNA's). There are many types of RNA's: especially important are the
newly discovered 'messenger' or 'informational' RNA's (Brenner et ah,
1961 ; Gros et al., 1961 ; Hayashi and Spiegelman, 1961, etc.). Messenger
ΐ Monsieur Jourdain: par ma foi! il y a plus de quarante ans que je dis la prose sans
que j'en susse rien, et je vous suis le plus obligé du monde de m'avoir appris cela. (Molière
1670.) 'Le Bourgeois gentilhomme'. Acte II, scène 4.
247
IN MORPHOGENESIS (AMPHIBIAN
EGG DEVELOPMENT.
REGENERATION IN
ACETABULARIA)
JEAN BRÄCHET
Faculté des Sciences, Université libre de Bruxelles, Belgium
I. Introduction
247
II. DNA in Amphibian Eggs and Acetabularia
249
A. Amphibian Egg Development
249
B. Acetabularia
256
III. RNA Distribution and Synthesis in Amphibian Eggs and Acetabularia
259
A. Amphibian Egg Development
259
Β. Acetabularia
268
IV. Sulphydryl Groups and Morphogenesis
274
A. Introductory Remarks
274
B. The Effects of j3-Mercaptoethanol on Morphogenesis
275
C. The Effects of α-Lipoic Acid on Morphogenesis (Amphibian Eggs and
Acetabularia)
283
D. Biochemical Effects of j3-Mercaptoethanol on Developing Organisms
286
V. Discussion
290
References
297
I. Introduction
It is the aim of chemical embryology to explain the intricate processes
of differentiation in terms of the synthesis and properties of the molecules
which build up the embryo: chemical embryologists have been
'molecular biologists', but without knowing it, long before molecular
biology became fashionable.f
Under the powerful impact of biochemical genetics, molecular biology
has been mainly concerned with the nature and transfer of genetic
information. It is now generally admitted that the genetic material is
deoxyribonucleic acid (DNA), which ultimately controls the synthesis of
specific proteins, enzymes or haemoglobin for instance. This control is,
however, indirect, and intermediates must exist between DNA and the
protein which is being built : these intermediates are the ribonucleic acids
(RNA's). There are many types of RNA's: especially important are the
newly discovered 'messenger' or 'informational' RNA's (Brenner et ah,
1961 ; Gros et al., 1961 ; Hayashi and Spiegelman, 1961, etc.). Messenger
ΐ Monsieur Jourdain: par ma foi! il y a plus de quarante ans que je dis la prose sans
que j'en susse rien, et je vous suis le plus obligé du monde de m'avoir appris cela. (Molière
1670.) 'Le Bourgeois gentilhomme'. Acte II, scène 4.
247