Porter and Bailey: Using measurements of muscle cell nuclear RNA to assess larval condition of Gadus chalcogrammus 
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Figure t 
(A) Scatter plot of 4',6-diamidino-2-phenylindole (DAPI) area (DNA content, linear 
scale) and DAPI height (DNA content, linear scale) for a laboratory-reared larva of 
Walleye Pollock (Gadus chalcogrammus ) sampled in 2009, showing the gating strat- 
egy used to exclude debris, doublets, triplets, and large aggregates from muscle cell 
nuclei in the GO and G1 (G0/G1), S, and G2 and M (G2/M) phases of the cell cycle. 
Those nuclei are enclosed within the gate, which is represented by a rectangle. (B) 
Histogram showing the distribution pattern of the nuclei within the gate. Phases of 
the cell cycle: Gl=gap 1 or cell growth before cell division, G0=resting state from Gl, 
S=DNA synthesis, G2=gap 2 or cell growth before mitosis, and M=mitosis. 
A gate that divided Gl-phase nuclei into fractions 
of low and high nRNA content on the basis of nRNA 
fluorescence of S-phase nuclei was made by follow- 
ing Staiano-Coico et al. (1989). The smallest value of 
S-phase nRNA fluorescence was the minimum nRNA 
content needed for Gl nuclei to enter the S phase, and 
it was assumed that any nuclei with greater fluores- 
cence also could enter the S phase (Staiano-Coico et al., 
1989). A gate that enclosed Gl nuclei was made, begin- 
ning at the smallest nRNA fluorescence value of the 
S-phase nuclei and extending to enclose the Gl nuclei 
with the highest nRNA fluorescence values (designated 
GIB; Fig. 3, A and B). The GIB group was defined 
as the number of nuclei with the potential to progress 
from the Gl to S phase. The number of S-phase nuclei 
was determined through the use of a gate that enclosed 
those nuclei (Fig. 3, A and B), and RSG1 was calculated 
by dividing that number by the number of GIB nuclei. 
