Yeast - Reference Chromosome I


Proc Natl Acad Sci U S A 92: 3809-3813 (1995) [95249563]

The nucleotide sequence of chromosome I from Saccharomyces cerevisiae.

H. Bussey, D. B. Kaback, W. Zhong, D. T. Vo, M. W. Clark, N. Fortin, J. Hall, B. F. Ouellette, T. Keng, A. B. Barton, S. Yuping, C. J. Davies and R. K. Storms

Biology Department, McGill University, Montreal, QC, Canada.

Chromosome I from the yeast Saccharomyces cerevisiae contains a DNA molecule of approximately 231 kbp and is the smallest naturally occurring functional eukaryotic nuclear chromosome so far characterized. The nucleotide sequence of this chromosome has been determined as part of an international collaboration to sequence the entire yeast genome. The chromosome contains 89 open reading frames and 4 tRNA genes. The central 165 kbp of the chromosome resembles other large sequenced regions of the yeast genome in both its high density and distribution of genes. In contrast, the remaining sequences flanking this DNA that comprise the two ends of the chromosome and make up more than 25% of the DNA molecule have a much lower gene density, are largely not transcribed, contain no genes essential for vegetative growth, and contain several apparent pseudogenes and a 15-kbp redundant sequence. These terminally repetitive regions consist of a telomeric repeat called W', flanked by DNA closely related to the yeast FLO1 gene. The low gene density, presence of pseudogenes, and lack of exp ression are consistent with the idea that these terminal regions represent the yeast equivalent of heterochromatin. The occurrence of such a high proportion of DNA with so little information suggests that its presence gives this chromosome the critical length required for proper function.

Note: The current version of chromosome I has been assembled from the latest updates available for this chromosome in EMBL/GENBANK and two additional submissions for the left and the right telomere sequenced by Rolf Wambutt et al. and Howard Bussey et al., respectively, on DNA provided by Ed Louis.

sequence left telomere: 2669 nt; overlap to U12980: 78 nt

U12908: 103674 nt; overlap to L05146: 132 nt

L05146: 29410 nt; overlap to L22015: 2000 nt

L22015: 41987 nt; overlap to L28920: 147 nt

L28920: 53840 nt; overlap to sequence right telomere: 365 nt

sequence right telomeric : 1337 nt


Total length: 230195 nt