The genes for ribosomal RNA and their transcription during amphibian development.

摘要: Publisher Summary This chapter mentions several criteria that are necessary to characterize a useful assay system with which study the regulation of transcription. The aims apply these ribosomal RNA's and genes define their structure in higher organisms. Particular emphasis is placed on information gained from oocytes embryos toad Xenopus laevis. way rRNA synthesized provides proof for two different theories control gene action. most popular theory today, is, “differential activity,’’ supported by marked variation synthesis occurs at stages embryogenesis adult tissues under conditions where invariable. However, second mechanism controls rate appears take place oocytes. In single cells, there has been an amplification rDNA. example genetic coupled well-known instances rhromosome diminution comprises transcription can be called “gene alteration.”