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A contiguous 60 kb genomic stretch from barley reveals molecular evidence for gene islands in a monocot genome.

ABSTRACT: The contiguous DNA sequence of a 60 kb genomic interval of barley chromosome 4HL has been assembled. The region harbours a single and novel gypsy -like retrotransposon, designated BAGY-1. Only three genes appear to reside in the genomic stretch. One predicts a plant homologue of ribophorin I, a subunit of the oligosaccharyltransferase-protein complex located in the rough endoplasmatic reticulum. The second is similar to the Drosophila g1 gene encoding a ring finger protein involved in developmental processes. The observed gene density is approximately 5-fold lower than in the best characterized dicot genome of Arabidopsis but 6- to 10-fold higher than expected from an equidistant gene distribution in the complex barley genome. Our data suggest that the 60 kb genomic interval represents part of a gene island, a seemingly distinctive feature of grass genomes.

SUBMITTER: Panstruga R

PROVIDER: S-EPMC147355 | biostudies-other | 1998 Feb

REPOSITORIES: biostudies-other

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A contiguous 60 kb genomic stretch from barley reveals molecular evidence for gene islands in a monocot genome.

Panstruga R R Büschges R R Piffanelli P P Schulze-Lefert P P

Nucleic acids research 19980201 4

The contiguous DNA sequence of a 60 kb genomic interval of barley chromosome 4HL has been assembled. The region harbours a single and novel gypsy -like retrotransposon, designated BAGY-1. Only three genes appear to reside in the genomic stretch. One predicts a plant homologue of ribophorin I, a subunit of the oligosaccharyltransferase-protein complex located in the rough endoplasmatic reticulum. The second is similar to the Drosophila g1 gene encoding a ring finger protein involved in developmen ...[more]

PMID: 9461468

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