Relative Effect of Transcription-Level and Translation-Level Control of Protein Synthesis during Early Development of the Sea Urchin

Abstract

Abstract. Newly synthesized proteins were pulse labeled with radioactive amino acids at several developmental stages of the sea urchin, Arbacia punctulata-in normal embryos and in embryos continuously exposed to the drug Dactinomycin. The soluble proteins were fractionated by electrophoresis through polyacrylamide gels. A simple procedure for complete solubilization of the proteins in slices of gels into a solution of toluene for liquid scintillation counting, and a computer program to display and to compare statistically the distributions of 14CC-and 3H-labeled proteins fractionated on the same gel, allowed quantitative statements to be made on the relative changes in protein synthesis. The conclusion is that translation-level control provides most of the changes in protein synthesis that occur between fertilization and hatched blastula stage.The control of the relative rates of synthesis of different proteins is now known to take place at the translational level in animal cells1 as well as at the transcriptional level.2 The existence of preformed cytoplasmic messenger RNA's in unfertilized sea urchin eggs3 prompted investigations on whether the pattern of protein synthesis could change in the absence of any new RNA synthesis, that is, whether differential utilization of the maternal messenger RNA could take place. The results of Terman and Gross4 established translation-level control of protein synthesis, in this sense, by a comparison of autoradiograms of polyacrylamide gels in which radioactive proteins were fractionated. The use of autoradiography and gel electrophoresis provided higher resolution than an independent study employing column chromatography5 or an earlier study6 utilizing a crude method to slice and to solubilize proteins in the gels, but the subjective nature of the interpretation of autoradiographic data limited the analysis to simple comparisons. The techniques used in the studies reported here allow a quantitative evaluation of the over-all difference, and a means of detecting where, and in what direction, differences occur between pairs of distributions of radioactive proteins. Statements can then be made concerning the relative contributions of transcription-and translation-level control of protein synthesis during early development.

Organization, Transcription, and Regulation in the Animal Genome

“…Extensive claims continue to be made for the importance of both translational control and control of the mRNA population through post-transcriptional intranuclear processing. It is clear that at least in embryological systems some form or forms of translation level control play a very significant role (e.g., Ecker and Smith, 1971;Terman, 1970;Ilan and Ilan, 1971). Obviously, all of these as well as various other modes of regulation may coexist.…”

Widespread uncoupling between transcriptome and translatome variations after a stimulus in mammalian cells

“…Originally studied in early stages of development in oocytes and embryos [1,2], translational control has been increasingly recognized as a very general feature of eukaryotic cells, extensively present also in mature tissues. This process is orchestrated by incoming cell stimuli which elicit largely unknown transduction pathways, affecting primarily translation initiation, i.e.…”

“…In the flow of genetic information, translational control is the level at which reprogramming of cell activities accesses the phenotype, ultimately shaping protein synthesis and therefore, together with the control of protein degradation, quantitative variation of the proteome. Originally studied in early stages of development in oocytes and embryos [ 1 , 2 ], translational control has been increasingly recognized as a very general feature of eukaryotic cells, extensively present also in mature tissues. This process is orchestrated by incoming cell stimuli which elicit largely unknown transduction pathways, affecting primarily translation initiation, i.e.…”

Integrated Translatome and Proteome: Approach for Accurate Portraying of Widespread Multifunctional Aspects of Trichoderma

“…The translatome referring to the active mRNAs population associated with ribosomes has facilitated the removal of background noise and useful for the accurate determination of active mRNA. Originally used in oocytes and embryos ( Terman, 1970 ; Gurdon et al, 1971 ), translational control has emerged as a key point of eukaryotes. The process is executed by loading of ribosomes on mRNA followed by translation elongation ( Groppo and Richter, 2009 ; Jackson et al, 2010 ).…”