PubMed Health⌕ Search

Biomedical subjects

Debbie K Goode

Publications and source records attributed to Debbie K Goode.

3 recordsLinked to original sources

Highly conserved regulatory elements around the SHH gene may contribute to the maintenance of conserved synteny across human chromosome 7q36.3.

Comparative genomic analysis reveals an exceptionally large section of conserved shared synteny between the human 7q36 chromosomal region and the pufferfish (Fugu rubripes) genome. Remarkably, this conservation extends not only to gene order across 16 genes, but also to the position and orientation of a number of prominent conserved noncoding elements (CNEs). A functional assay using zebrafish has shown that most of the CNEs have reproducible and specific enhancer activity. This enhancer activity is often detected in a subset of tissues which reflect the endogenous expression pattern of a proximal gene, though some CNEs may act over a long range. We propose that the distribution of CNEs, and their probable association with a number of genes throughout the region, imposes a critical constraint on genome architecture, resulting in the maintenance of such a large section of conserved synteny across the vertebrate lineage.

Animals↗

Highly conserved non-coding sequences are associated with vertebrate development.

In addition to protein coding sequence, the human genome contains a significant amount of regulatory DNA, the identification of which is proving somewhat recalcitrant to both in silico and functional methods. An approach that has been used with some success is comparative sequence analysis, whereby equivalent genomic regions from different organisms are compared in order to identify both similarities and differences. In general, similarities in sequence between highly divergent organisms imply functional constraint. We have used a whole-genome comparison between humans and the pufferfish, Fugu rubripes, to identify nearly 1,400 highly conserved non-coding sequences. Given the evolutionary divergence between these species, it is likely that these sequences are found in, and furthermore are essential to, all vertebrates. Most, and possibly all, of these sequences are located in and around genes that act as developmental regulators. Some of these sequences are over 90% identical across more than 500 bases, being more highly conserved than coding sequence between these two species. Despite this, we cannot find any similar sequences in invertebrate genomes. In order to begin to functionally test this set of sequences, we have used a rapid in vivo assay system using zebrafish embryos that allows tissue-specific enhancer activity to be identified. Functional data is presented for highly conserved non-coding sequences associated with four unrelated developmental regulators (SOX21, PAX6, HLXB9, and SHH), in order to demonstrate the suitability of this screen to a wide range of genes and expression patterns. Of 25 sequence elements tested around these four genes, 23 show significant enhancer activity in one or more tissues. We have identified a set of non-coding sequences that are highly conserved throughout vertebrates. They are found in clusters across the human genome, principally around genes that are implicated in the regulation of development, including many transcription factors. These highly conserved non-coding sequences are likely to form part of the genomic circuitry that uniquely defines vertebrate development.

Animals↗

Comparative analysis of vertebrate Shh genes identifies novel conserved non-coding sequence.

The puffer fish Takifugu rubripes (Fugu), with its compact genome, is an ideal model organism for comparative genomics. Sonic hedgehog (Shh) is a key protein in the patterning of differentiating cells during embryonic development. We have sequenced the Fugu Shh gene and compared it with the mammalian and zebrafish orthologs, identifying a number of novel conserved, non-coding sequences upstream of exon one and within the two introns. Additional conserved sequences serve to delineate activator regions and enhancers previously characterized through functional analysis. Control elements can thus be rapidly and effectively predicted by comparative methodology in its own right as well as complementing other, functional methods. This work demonstrates the value of using Fugu in comparative genomics, which has allowed identification of new putative regulatory elements, as well as corroborating enhancers identified by the more traditional deletion mapping method.

Animals↗