Vertebrate genomes

Hedges SB, Kumar S Vertebrate genomes compared. Science 2002 297 1283. (The same issue—No. 5585, August 23— contains a draft version of the genome of the tiger puffer fish.)... 

Sandelin, A., Bailey, P., Bruce, S., et al. (2004) Arrays of ultraconserved non-coding regions span the loci of key developmental genes in vertebrate genomes. BMC Genomics. 5,99. 

Fig. 2. Distribution of methylated CpGs in genomic DNA and their effect on transcription. 70-80% of all CpG dinucleotides are methylated in vertebrate genomes. mCpGs (filled lollipops) are randomly distributed throughout the genome but are excluded from regions with unusually high CpG density—CpG islands [16,17]. Most of the CpG islands are associated with gene promoters and maintained unmethylated (white lollipops) in all types of somatic cells. Aberrant methylation of CpG islands occurs in cancer cells and leads to silencing of tumor-suppressor and other essential genes [19-21].

Gardiner-Garden, M. and Frommer, M. (1987) CpG islands in vertebrate genomes. Journal of Molecular Biology, 196, 261-282. 

Comparative (Zoo-FISH) genome mapping and positional cloning of evolutionary chromosome breakpoints in important mammal and vertebral genomes... 

Cloning and characterization of the gene for hypertension and brachydactyly on the short arm of chromosome 12 Comparative physical and transcriptional mapping of human chromosome 20ql3 segment as candidate for imprinting MITOP - the mitochondria project Molecular analysis of the vertebrate genome... 

The presence of retrotransposon-derived repetitive DNA in such abundance in mammalian genomes is a mystery in terms of its origin as well as its role in the evolution of the genomes it inhabits. These mysteries will best be solved by detailed comparative studies of a number of elements in an evolutionary context. Already, phylogenetic analysis has led to an improved understanding of the structure and dynamics of retrotransposi-tion of LINE and SINE elements of vertebrate genomes.4 11 12 22-24 We have detailed three useful methods for the isolation of interspersed repetitive... 

Panopoulou G, Poustka AJ. Timing and mechanism of ancient vertebrate genome duplications—the adventure of a hypothesis. Trends Genetics 2005 21 559-567. 

Table 2. Coronin repertoires and anomalies in selected vertebrate genomes...

Morita Y, Finger TE (1998) Differential projections of ciliated and microvillous olfactory receptor cells in the catfish, Ictalurus punctatus. J Comp Neurol 398 539-550 Nakatani Y, Takeda H, Kohara Y, Morishita S (2007) Reconstruction of the vertebrate ancestral genome reveals dynamic genome reorganization in early vertebrates. Genome Res 17 1254-1265... 

Brenner S, Elgar G, Sandford R, Macrae A, Venkatesh B, Aparicio S (1993) Characterization of the pufferfish (Fugu) genome as a compact model vertebrate genome. Nature 366 265-268... 

In contrast, vertebrate genomes contain many sequences that do not code for RNAs or have any structural or regulatory function. Much of this nonfunctional DNA is composed of repeated sequences. In humans, only about 1.5 percent of total DNA (the exons) actually encodes proteins or functional RNAs. 

Cytochrome P-450 is a name for a family of heme proteins that perform hydroxylation reactions, as well as epoxidation, peroxygenation, desulfuration, dealkylation, deamination, and dehalogenation reactions. Most vertebrate genomes contain more than 40 different structural genes for cytochrome P-450. The proteins resemble mitochondrial cytochrome oxidase in being able to bind both 02 and carbon monoxide. Cytochrome P-450 proteins are usually found in the endoplasmic reticulum of eukaryotic cells. 

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