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Updated: May 12, 2026

RNA In situ Hybridization in Whole Mount Embryos and Cell Histology Adapted for Marine Elasmobranchs
Published on: April 12, 2013
Properties of sea urchin embryo messenger RNA containing and lacking poly(A)
Abstract:
Various properties of nonhistone messenger RNA species containing poly(A), [+A]mRNA, and lacking poly(A), [-A]mRNA, are described: the rates of turnover of these mRNA classes are not significantly different, as indicated by their similar rates of entry into and decay from the cytoplasm; each mRNA class is essentially entirely transcribed from unique DNA sequences; the ratio of [+A] to [-A] nonhistone mRNA increases with increase in size of free polyribosome, although the average molecular weights of these mRNAs are similar in each polysomal size class. These results indicate that the [+A]mRNA species tend to be more fully loaded with ribosomes than the nonhistone [-A]mRNA species.
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