The revolution of the biology of the genome

Sequence data of entire eukaryotic genomes and their detailed comparison have provided new evidence on genome evolution. The major mechanisms involved in the increase of genome sizes are polyploidization and gene duplication.Subsequent gene silencing or mutations,preferentially in regulatory sequences of genes,modify the genome and permit the development of genes with new properties. Mechanisms such as lateral gene transfer,exon shuffling or the creation of new genes by transposition contribute to the evolution of a genome,but remain of relatively restricted relevance.Mechanisms to decrease genome sizes and,in particular,to remove specific DNA sequences,such as blocks of satellite DNAs,appear to involve the action of RNA interference (RNAi). RNAi mechanisms have been proven to be involved in chromatin packaging related with gene inactivation as well as in DNA excision during the macronucleus development in ciliates.

作 者： Wolfgang Hennig   作者單位： German Academic Exchange Service (DAAD) Laboratory,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,320 Yue Yang Road,Shanghai,200031,China  刊 名： 細(xì)胞研究(英文版)  ISTIC SCI 英文刊名： CELL RESEARCH  年，卷(期)： 2004 14(1)  分類(lèi)號(hào)： Q2  關(guān)鍵詞： genome structure   gene duplication   RNAi   gene silencing   chromatin