Chapter 13: Differentation - Endnotes
Schierenberg, E. "Cell Determination during Early
Embryogenesis of the Nematode Caenorhabditis elegans." in
Molecular Biology of Development: Cold Spring Harbor Symposia on
Quantitative Biology, Vol L, Cold Spring Harbor Laboratory, Cold
Spring Harbor, 1985. pp. 59-68.
Hirsh, D. K.J. Kemphues, D.T. Stinchcomb and R.
Jefferson. "Genes Affecting Early Development in Caenorhabditis
elegans." Molecular Biology of Development: Cold Spring Harbor
Symposia on Quantitative Biology, Vol L, Cold Spring Harbor
Laboratory, Cold Spring Harbor, 1985. pp. 69-78.
Sulston, J.E., E. Schierenberg, J. White, and N.
Thomson. 1983. "The Embryonic cell lineage of the nematode
Caenorhabditis elegans". Dev. Biol. 100:64.
Fixsen, W., P. Sternberg, H. Ellis and R. Horvitz.
"Genes That Affect Cell Fates during the Development of
Caenorhabditis elegans". in Molecular Biology of
Development: Cold Spring Harbor Symposia on Quantitative Biology,
Vol L, Cold Spring Harbor Laboratory, Cold Spring Harbor, 1985.
Sobota A.E. and Partanen, C.R. 1966. "The growth and
division of cells in relation to morphogenesis in fern
gametophytes. I. Photomorphogenetic studies in Pteridium
aquilinum". Canad. Jour. Bot. 44:497-506.
Miller, J.H., and Miller, P.M. 1961. "The effect of different
light conditions and sucrose on the growth and development of
the fern, Onoclea sensibilis" Amer. Jour. Bot.
Davis, B.D. 1968. "Effect of light quality on the transition to
two-dimensional growth by gametophytes of Pteridium
aquilinum". Bulletin Torrey Bot. Club 95:31-36.
Bonner, J.T. 1947. J. Exp. Zool. 106,1.
Bonner, J.T. 1967. The Cellular Slime Moulds. 4,
Princeton University Press, Princeton.
Bonner, J.T., Chiquoine, A.D. and Kolderie, M.Q. "A
Histochemical study of Differentiation in the Cellular Slime
Molds". J. Exp. Zool. 130:133-157. 1955.
R.R. Sussman and M. Sussman have the most extensive list of
publications, much too long to list. For reference, see
Sussman, M. "Biochemical and Genetic Methods in the Study of
Cellular Slime Mold Development." In Methods in Cell Physiology.
D. Prescott, ed. Academic Press, New York, 1966.
Ashworth, J.W. 1974. "The Development of the Cellular Slime Moulds"
in Biochemistry of Cell Differentiation
(J. Paul, ed.), Biochemistry Series One, Vol. 9, MTP International
Review of Science. University Park Press (Butterworths, London),
Baltimore, 1974. pp. 7-34.
For an excellent mathematical treatment of this topic, refer
to Segel, L.A. Modeling dynamic phenomena in molecular
and Cellular Biology, Cambridge University Press,
Cambridge, 1984, pp. 97-129.
Wang, Mei and P. Schaap. "Correlations between Tip Dominance,
Prestalk/Prespore Patterns and cAMP relay efficiency in Slugs
of Dictyostelium discoideum." Differentiation 30:7-14.
J.T. Bonner. "Induction of Stalk Cell Differentiation
by Cyclic AMP in the Cellular Slime Mold Dictyostelium
discoideum". Proc. Nat. Acad. Sciences.
65(1) Jan. 1970. pp. 110-113.
Unfortunately there is no external means of
determining gender of the sea urchin. When Strongylocentrotus
purpuratus is induced to shed gametes, the eggs that are
released will be a yellow color, while the sperm is white. Thus,
the gender is determined via the gametes that are released.
For assistance in your drawings, excellent photographs of early
embryology are found in Mathews, Wills W. Atlas of Descriptive
Embryology, 3rd Ed. Macmillan, New York, 1982.
If long term obsrvation is desired, a special slide needs to be made.
Place masking tape on a slide, with a hold cut in the middle. Put a
small drop of liquified NG agar on the slide and place a siliconized
coverslip immediately on the agar. When the agar solidifies, remove
the coverslip. Just prior to use, place a very small amount of E.
coli on the agar, transfer a worm to the agar, and place a
coverslip over the agar and the tape. Once the worm takes to eating
the bacteria, it will settle down and can be readily observed for hours.
Use Normarski interference optics if available. Otherwise alternate
between bright field and dark field views.
For a thorough review of the hematopoietic system, refer to Junqueira,
L.C., J. Carneiro, and A.N. Contopoulos. Basic Histology.
Lange Medical Publications, Los Altos, 1975.
Although Knop's is more commonly used, the author has used Knudson's
for many years. Any minimal plant media with minor and major salts
will work. The critical factor is low pH, with an ideal of about 5.5.
If organic elements are added (such as sucrose) then the media must
be sterilized to prevent the growth of fungi. Sterility is not
required if the organic elements are eliminated, and the fern spores
will germinate extremely well. In fact they will germinate reasonably
well on the surface of a clay flower pot that is kept moist with
plain tap water.
Photomorphogenesis depends on the quality of these filters. Many
lightly colored filters allow transmission of significant amounts of
light other than the color they appear to be. To check, cut a small
piece of the cellophane and tape it to a spectrophotometer cuvette.
Run an absorption spectrum on the cellophane to identify the
wavelengths which are transmitted.
Alternatively, the agar media can be put in baby food jars, the
spores placed on the agar, the tops sealed with plastic wrap and
held in place by a rubber band. This system will allow the
gametophytes to develop completely over periods greater than 6
months, and will even support the early growth of the sporophyte.
By contrast, the petri plates are useful only for about two weeks.
Firtel, R.A. and J.T. Bonner. "Characterization of the genome of
the cellular slime mold Dictyostelium discoideum." J.
Mol. Biol. 66:339-361. 1972. This culture has the advantage
of easy administration of cAMP and differentiation can be controlled
to some extent by the speed with which the amoeba are shaken. Slow
speeds allow the amoeba to form aggregates, while higher speeds
impede this formation.
Further differentiation can be had by "pulsing" the cultures
with cAMP. In the normal aggregation and development of the
slime mold, the cells do not continuously secrete cAMP, but
secrete it in increasing measured doses.
Reymond, et al. Cell 39:1984.
Ratner, D. and W. Borth. "Comparison of Differentiating
Dictyostelium discoideum Cell Types Separated by an
Improved Method of Density Gradient Centrifugation". Exper.
Cell Research 143 (1983) p. 1-13.
Ratner, D. and Borth W. 1982. "Comparison of differentiating
Dictyostelium discoideum cell types separated by an
improved method of density gradient centrifugation." Exp.
Cell Res. 143;1-13. 1983.
If the slugs do not readily dissociate, 12.5 mM
2,3-dimercaptopropanol and 1 mg/ml pronase may be added.
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Cell Biology Laboratory Manual
Dr. William H. Heidcamp, Biology Department, Gustavus Adolphus College,
St. Peter, MN 56082 -- firstname.lastname@example.org