Denis Brachet (1 results)

Pamphlet. Condition: Very Good. Prompt Shipment, shipped in Boxes, Tracking PROVIDEDOffprint. This is precisely what Herman Denis did during a stay a few yearslater at Jean Brachet's lab at the LlGBin Naples. He showed thatRNAsynthesized by an interspecific sea urchin hybrid blocked at thegastrula stage is preponderantly paternal, despite the preferentialelimination of paternal chromosomes during egg cleavage. Withelegant saturation and competition experiments using molecularhybridization on filt~rs. he explained the paradox by the existenceof two classes of genes that become active at the onset ofgastrulation, The first and most abundant class of genes, destinedto be expressed at all stages of development, are normally subjectto negative control, which a foreign cytoplasm cannot exert. Thesecond group of genes. which are functional only during the earlydevelopmental stages. fail. on the other hand. to be activated in thesame foreign cytoplasm. These outstanding results already underlinethe full importance of the activation and repression of genesexerting specific control over the stages of morphogenesis. They were published in 1969 and 1970, in three papers signed H. Denisand J. Brachet that received much attention."Jean Brachet and his School by HENRI ALEXANDRE Int. J. Dev Biol. 36: 29-41 (1992) First separate edition. Offprint. Original wrappers.*. First edition. Signed inscribed presentation.