| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Biology, Princeton University, Princeton, New Jersey 08540
1. It has been shown that there is a substance (or substances) given off by the cellular slime mold amoebae that both orients aggregating cells ( e. g. in the Shaffer test) and increases the rate of movement of the cells. A simple, quantitative assay has been developed to test the rate of cell movement. Using both types of test in conjunction, we have been able to show that the substance(s) is produced before the aggregation of the amoebae and is even present in large amounts in the food source, E. coli.
2. The substance(s) is not species-specific; it induces adhesiveness in cells approaching aggregation; it does not affect center formation or center inhibition (territory size); nor is it related to the phenomenon of cell repulsion.
3. It is quite possible that there are many substances involved and the rate-increasing substance (s) is separate from orientation substance(s). Another possibility is that they are all one substance, which has hitherto been called acrasin. If this is the case then aggregation can no longer be considered the moment of first acrasin secretion, but one would have to assume that it is the moment of first acute sensitivity to acrasin, a sensitivity sufficient to override the cell repulsion phenomenon. It is hoped that if the chemical identification of the rate substance is achieved, then many of these important questions will be answered.
This article has been cited by other articles:
|
|
 |
|
  A. Robertson, D. J. Drage, and M. H. Cohen Control of Aggregation in Dictyostelium discoideum by an External Periodic Pulse of Cyclic Adenosine Monophosphate Science, January 21, 1972; 175(4019): 333 - 335. [Abstract] [PDF]
|
|
|
|
|
|
D. S. Barkley Adenosine-3', 5'-Phosphate: Identification as Acrasin in a Species of Cellular Slime Mold Science, September 12, 1969; 165(3898): 1133 - 1134. [Abstract] [PDF]
|
|
|
|
|
|
Y.-Y. Chang Cyclic 3',5'-Adenosine Monophosphate Phosphodiesterase Produced by the Slime Mold Dictyostelium discoideum Science, July 5, 1968; 161(3836): 57 - 59. [Abstract] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
