To quantify the proportion of ribosomes in the monoribosome (monosome) and polyribosome (polysome) fractions, sucrose gradients with an EDTA-containing cushion were used to accumulate all of the different size classes of polysomes (measured as one large peak).
Table 1 Percent of ribosomes in polysomes for developmental stagesof the Antarctic sea urchin Sterechinus neumayeri Developmental stage Percent ribosomes in polysomes ([+ or -]SE) Blastula (n = 4) 45.
The protocols employed in this study allowed for the reliable separation of polysomes from monosomes and the effective radioactive labeling with amino acids of nascent peptides still attached to polysomes (Fig.
At steady-state radioactive labeling of the polysomes, the rate of incorporation of radioactive amino acids should be similar for the total amount of radioactive amino acids in peptides (the sum of radioactivity in the nascent and completed peptide fractions) and for radioactivity in the completed peptide fraction only.
purpuratus, the percent of ribosomes in polysomes has also been reported to be low, ranging from 0% to 5% (Infante and Nember, 1967; Goustin and Wilt, 1981).
lower sensitivity UV absorption) showed that the maximum discernible number of ribosomes in polysomes of embryos of S.
However, the presence of clear vesicles, some of them associated with polysomes
, could indicate the existence of other secretory processes in the life cycle, as seen by the extrusion of a clear vesicle close to a synaptic button (Fig.
As a result of larger genetic diversities, higher affinity binders are found with polysomes than with phage display.
From the literature, it appears that a peptide binding the thrombopoietin (TPO) receptor has been produced by this method, and at least two other research organizations are displaying and selecting antibodies from polysomes made in vitro.
The biotechnology firm is focused on the use of polysome methods to isolate molecules that bind specific targets and to engineer proteins for improved or novel activities.
Taken together, our observations indicate that the large nerve endings of the squid photoreceptor neuron contain a system of eukaryotic polysomes
whose activity is modulated by exposure of the squid to a light or dark environment.
In preliminary analyses, the radiolabeled translation products of synaptosomal polysomes
immunoabsorbed by a specific NF antibody display a prevalent 70S component, in agreement with the behavior of intact synaptosomes, but at variance with the pattern of the translation products of microsomal polysomes