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. Author manuscript; available in PMC: 2014 Jul 14.
Published in final edited form as: Dev Biol. 1981 Aug;86(1):241–249. doi: 10.1016/0012-1606(81)90336-5

TABLE 1.

Distribution of [3H]RNA in Ribosomal Fractions of S. purpuratus eggs and early embryos

Expt Stage Percentage
inhibitiona
with
emetine		 Number of
transits in
emetineb 		Percentage [3H]RNAc
Polyribosomes
Monoribosomes Small Large
1. UF eggs Control (4) 83.5 ± 0.9 10.1 ± 0.7   6.4 ± 0.7
UF eggs 90−70 0.61 82.5 11.5   6.1
UF eggs 90−70 1.63 82.9 10.8   6.3
2. Zygotesd Control 69.1 13.1 17.7
2-celle Control 66.8 13.9 19.2
2-cellf 75−40 2.3 65.8 17.5 16.6
4-cellg Control 66.1 15.1 18.9
4-8-cellh 75−40 5.0 66.3 15.1 18.6
8-16-celli Control 65.2 15.1 19.7
16-cellj 75−40 6.4 66.9 14.6 18.4
3. Early Blk Control (3) 58.9 ± 0.8 22.3 ± 1.0 18.8 ± 0.4
Early Blk 72−49 1.3 48.0 26.8 25.2
a

Controls had no emetine present. Emetine was added to a final concentration of 1.5 and 8.0 µM for treated cultures of unfertilized eggs (UF eggs) and embryos, respectively. The percentage inhibition was monitored during the experiments (see Figs. 1 and 2). The number of independent gradients is indicated in parentheses. Average experimental variation is given.

b

The number of transits was calculated from the percentage inhibition and the known transit times were adjusted for incubation at 14°C (Hille and Albers 1979; Brandis and Raff 1978).

c

80 S includes subunits, monoribosomes, and the dimer region. Small polyribosomes include those containing three to seven ribosomes; large polyribosomes those containing eight or more ribosomes.

d–k

The culture age at 14°C and stages at which polyribosome profiles were measured are d 1.5 hr, nuclei condensing; e 2.5 hr, 83% 2-cell, 15% 4-cell;f 4.2 hr, 65% 2-cell, 35% 4-cell; g 3.5 hr, 88% 4-cell, 12% 2-cell; h 6.1 hr, 39% 4-cell, 44% 8-cell, 17% 16-cell; i 4.7 hr, 32% 8-cell, 52% 16-cell; j 7.1 hr, 83% 16-cell, 17% 8-cell; k 10 to 12 hr, 1 hr postmorula or the earliest blastula stage detectable.