ShadowDance

The genome of the yeast Saccharomyces cerevisiae encodes 1500 so-called duplicate genes that exist in multiple copies (Gu et al. 2003), about 496 of which resulted from an ancient genome duplication (Dietrich et al. 2004; Kellis et al. 2004). Their role in compensating knockout mutations—often referred to as genetic network robustness—has been recognized (Pal 2001; Gu 2003; Gu et al. 2003; Blank et al. 2005), although others favor alternative pathways as the main reason that a substantial fraction of gene deletions do not yield a significant phenotype (Wagner 2000). This redundancy-robustness connection or back-up function, however, is not the evolutionary driving force that retains both gene copies. The reigning paradigm on the fate of duplicates predicts that one of the duplicates is either lost or gains a new function. Return to the single-copy state is then prevented by specialization in function, expression, and localization (neo- and subfunctionalization) (Ohno 1970; Kellis et al. 2004; Zhang and Kishino 2004;Presgraves 2005) or increased gene dosage to boost activity of key reactions (Seoighe and Wolfe 1999). More specifically, it has been suggested that many duplicates from the genome duplication played a direct role in the adaptation of S. cerevisiae toward fermentation, and thus were largely selected for in the domestication of yeast (Wolfe 2004).

Alternative splicing is a process by which the exons of the RNA produced by transcription of a gene (a primary gene transcript or pre-mRNA) are reconnected in multiple ways during RNA splicing. The resulting different mRNAs may be translated into different protein isoforms; thus, a single gene may code for multiple proteins[1].
Alternative splicing occurs as a normal phenomenon in eukaryotes, where it greatly increases the diversity of proteins that can be encoded by the genome[1]; in humans, over 80% of genes are alternatively spliced[2]. There are numerous modes of alternative splicing observed, of which the most common is exon skipping. In this mode, a particular exon may be included in mRNAs under some conditions or in particular tissues, and omitted from the mRNA in others[1].

На 15 април 2010 в НЦООЗ ще се проведе курс “Генетично модифицирани организми – прилагане на законодателството”. Курсът е ориентиран към търговци (вносители на суровини), производители и други специалисти от хранително-вкусовата промишленост.