The Characterization of Two New Clusters of Duplicated Genes Suggests a ‘Lego’ Organization of the YeastSaccharomyces cerevisiae Chromosomes

Abstract

The systematic sequencing of 42 485 bp of yeast chromosome VII (nucleotides 377948 to 420432) has revealed the presence of 27 putative open reading frames (ORFs) coding for proteins of at least 100 amino acids. The degree of redundancy observed is elevated since five of the 27 ORFs are duplications of a previously identified gene. These duplicated copies may be classified in two types of cluster organization. The first type includes genes sharing a significant level of identity in the amino acid sequences of their predicted protein product. They are recovered on two different chromosomes, transcribed in the same orientation and the distance between them is conserved. The second type of cluster is based on one gene unit tandemly repeated. This duplication is itself repeated elsewhere in the genome. The level of nucleic acid identity is high within the coding sequence and the non‐coding region between the two repeats. In addition, the basic gene unit is recovered many times in the genome and is a component of a multigene family of unknown function. These organizations in clusters of genes suggest a ‘Lego organization’ of the yeast chromosomes, as recently proposed for the genome of plants (Moore, 1995). The sequence is deposited in the Yeast Genome Databank under Accession Number from Z72562 to Z72586. © 1997 John Wiley & Sons, Ltd.

Genomic Exploration of the Hemiascomycetous Yeasts: 20. Evolution of gene redundancy compared to Saccharomyces cerevisiae

“…Similarly, S. cerevisiae contains multigene families for which we found no homologues in any of the 13 yeast species studied (see Table 1 in [17]). One of the most spectacular of them is the P26.1.f7.1 9‐gene family of unclear function [18]. The existence of, apparently, species specific gene families raises an interesting problem with regard to the origin of such sequences and to their expansion or loss in some species.…”

Genomic Exploration of the Hemiascomycetous Yeasts: 10.Kluyveromyces thermotolerans

“…Nevertheless, four large families are without representatives in K. thermotolerans and it is striking that they are located in the subtelomeric regions in S. cerevisiae (P24.1f23.1, P9.4f8.1 and P26.1f13.1 [19]) or correspond to the DUP family. The DUP family (10 members of unknown function) was studied by Feuermann et al [22] and corresponds to two clusters of tandem repeats on the right arm of S. cerevisiae chromosome I (six genes) and the left arm of chromosome VI (two members). The remaining two members of the DUP family are located as single copies on chromosomes III and VIII.…”

Gene Amplification of CYP51B : a New Mechanism of Resistance to Azole Compounds in Trichophyton indotineae

“…Gene duplications within genomes can be classified into two types of cluster organization ( 40 ). The first, most frequent type includes genes sharing a significant level of identity in the amino acid sequences of their predicted protein product and organized in a similar manner (synteny) on different parts of the genome.…”