Modification of Transfer RNA Levels Affects Cyclin Aggregation and the Correct Duplication of Yeast Cells.

Codon usage bias (the preferential use of certain synonymous codons (optimal) over others is found at the organism level (intergenomic) within specific genomes (intragenomic) and even in certain genes. Whether it is the result of genetic drift due to GC/AT content and/or natural selection is a topic of intense debate. Preferential codons are mostly found in genes encoding highly-expressed proteins, while lowly-expressed proteins usually contain a high proportion of rare (lowly-represented) codons.

Endogenous and Foreign Nucleoid-Associated Proteins of Bacteria: Occurrence, Interactions and Effects on Mobile Genetic Elements and Host's Biology.

Mobile Genetic Elements (MGEs) are mosaics of functional gene modules of diverse evolutionary origin and are generally divergent from the hosts´ genetic background. Existing biases in base composition and codon usage of these elements` genes impose transcription and translation limitations that may affect the physical and regulatory integration of MGEs in new hosts. Stable appropriation of the foreign DNA depends on a number of host factors among which are the Nucleoid-Associated Proteins (NAPs).

The Type IV Secretion System of ICE1: Formation of a Conjugative Pilus in .

The dispersal of mobile genetic elements and their gene cargo relies on type IV secretion systems (T4SS). In this work the ICE1 Tra-type T4SS nanomachine, encoded in the publicly available genome of ATCC 23270, was characterized in terms of its organization, conservation, expression and mating bridge formation. Twenty-one conjugative genes grouped in four genetic clusters encode the ICE1 T4SS, containing all the indispensable functions for the formation and stabilization of the pili and for DNA processing.