decision-making body since it is the first to 

 receive the challenge and is also the first one 

 to send out the request for change. We shall 

 avoid these opinionated arguments by simply 

 calling this category of decision-making proc- 

 esses the nuclear-cytoplasmic interdependent 

 process. 



This analysis brings out certain serious 

 complications. These workers who have mainly 

 been interested in the interlocking cycle located 

 in the cytoplasm have no easy way of studying 

 the biochemical nature of the cytoplasmic sig- 

 nals and the mechanism by which they are sent 

 to the nucleus. This is simply because it requires 

 a genetic-nuclear apparatus in order to detect 

 these signals. If such investigators are not 

 sxofficiently careful they also may not be able 

 to pick up the nuclear signals. In setting up the 

 experimental condition to study the cytoplasmic 

 cycle, the machinery of the cytoplasmic re- 

 sponse to the nuclear signals may not be kept 

 functional. Therefore, these workers may have 

 unknowingly narrowed their point of view to 

 only the cytoplasmic processes and completely 

 neglected the important relationships and inter- 

 dependency between the cytoplasm and the 

 nucleus. Those workers who, on the contrary, 

 have been mainly interested in the operation of 

 the genetic -nuclear apparatus, may not be aware 

 of the nature of the cytoplasmic signals, the 

 origin of the cytoplasmic perturbation or the 

 response of the cytoplasm to the nuclear com- 

 mand. Furthermore, our biochemical under- 

 standing of the nuclear events (the clockwise 

 circle in Scheme I) is comparatively rudimen- 

 tary. Reliable facts and concepts are few in 

 this area and they are hard to get. For instance, 

 we need to have a biochemical preparation of 

 nuclear apparatus which can respond to cyto- 

 plasmic signals. Perhaps, such a nuclear prep- 

 aration should synthesize new types of RNA 

 when given a dose of hormone. Until we are 

 sure about the nature of the cytoplasmic signals, 

 it will, however, be very difficult to prepare 

 such biochemical machinery responsive to these 

 signals in an in vitro experiment. When the 

 experimental result is negative, we don't know 

 whether the machinery is nonfunctional or 

 whether we have given the wrong signals. We 

 are, however, encouraged by the effort and the 

 results of Professor James Bonner's group in 

 this direction as presented by Dr. Roger 

 Chalkley. 



In summary, the main theme we have dis- 

 cussed so far is not much different from the 

 old idea in biology about a nuclear-cytoplasm 



relationship. However, we have redefined it in 

 a context more adaptable to our time. In doing 

 so, we have focused our attention on this rela- 

 tionship as the most important cellular factor 

 to be considered in developmental biology. We 

 hope this clarification will reduce the problem 

 of communication and will provide a proper 

 perspective about our own research as related 

 to biology as a whole. Hopefully, this may lead 

 to successful cooperation and fruitful exchange 

 of ideas. We have an appropriate example in 

 the workshop. The work of Dr. Edward Cantino 

 is more related to the cytoplasmic events of 

 the interesting water mold, Blastocladiella 

 emersonii. On the other hand, the work of Dr. 

 Lovett on this same organism is more con- 

 centrated on the function of the genetic nuclear 

 apparatus. In putting the story together from 

 their work, which undoubtedly they will do, we 

 may be able to get a more complete picture 

 about the intriguing mechanism of this creature 

 in making its decision for differentiation and 

 development. 



Now let us look into the future for the next 

 five years, say up to 1970. I think that the many 

 basic problems of developmental biology in 

 terms of biochemical hardware and mechanism 

 are solvable to us in the next five years with 

 sufficient manpower and financial resources. 

 There is no sign of a shortage in either cate- 

 gory. What I mean is that we do not need a 

 technological break-through before we can solve 

 these problems. For instance, we do not need 

 to wait for the development of an electron 

 microscopic movie camera, I think, rather, 

 that the biggest barrier in fact is educational 

 or communicational in nature. That is to say, 

 the chemists working with a system will not 

 know enough about the biology of the system 

 and the biologists working on other systems 

 will not know enough about their chemistry. 

 Even in the field of biochemistry, those who 

 work on nuclear events may overlook the cru- 

 cial points related to cytoplasm and those 

 who work at the cytoplasmic enzyme level may 

 neglect the pertinent facts derived from the 

 nucleus. We do need new ideas and ingenious 

 approaches in these fields. These inspirations 

 usually come from an organic synthesis of 

 various disciplines not brought together before. 

 This is why workshops of this type are so 

 valuable. 



Let's look ahead further into the coming 

 ten years, say up to 1975. What will be thinking 

 about? We saw a glimpse of that in this work- 

 shop. At that time, hopefully, we will know a 



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