Sixty years after Francis Crick enunciated the "Central dogma of molecular biology" many discoveries and new frontiers have taken places on the "functional" question of a genome, that is, how a DNA "speaks" to the livings. Today it is quite known as a genome "is", and discuss only with this structural question is cer-tainly very simplistic, at least certainly for the human DNA. It is instead the standard goal of these years to discover how and when a genome expresses itself, how it functionally translates itsown message, making this visible in the phenotypes of the living, regardless of its primary sequence of nitrogenous bases. It follows that the genetic code, still valid and almost universal among the livings, today represents only a small part of how a genome really is expressed. Today, there are at least two other known levels ofgenomic organization which at the same nucleotide sequences can associate different genetic expressions: i) epigenetics, with small RNAs now in the limelight, ii) nuclear architecture and chromosomal localization in an inter-phase nucleus. Experimental examples, educational comparisons and facilitated cognitive paths are described.
|Titolo della pubblicazione ospite||Atti della Scuola Permanente per l’Aggiornamento degli Insegnanti di Scienze Sperimentali “Messaggi di Scienza”|
|Numero di pagine||6|
|Stato di pubblicazione||Published - 2018|