Deletions in processed pseudogenes accumulate faster in rodents than in humans
- 74 Downloads
The relative rates of point nucleotide substitution and accumulation of gap events (deletions and insertions) were calculated for 22 human and 30 rodent processed pseudogenes. Deletion events not only outnumbered insertions (the ratio being 7∶1 and 3∶1 for human and rodent pseudogenes, respectively), but also the total length of deletions was greater than that of insertions. Compared with their functional homologs, human processed pseudogenes were found to be shorter by about 1.2%, and rodent pseudogenes by about 2.3%. DNA loss from processed pseudogenes through deletion is estimated to be at least seven times faster in rodents than in humans. In comparison with the rate of point substitutions, the abridgment of pseudogenes during evolutionary times is a slow process that probably does not retard the rate of growth of the genome due to the proliferation of processed pseudogenes.
Key wordsProcessed pseudogenes Rate of substitution Deletions Insertions Genome size
Unable to display preview. Download preview PDF.
- Benchimol S, Jenkins JR, Crawford LV, Leppard K, Lamb P, Williamson NM, Pim DC, Harlow E (1984) Molecular analysis of the gene for the p53 cellular tumor antigen. Cancer Cells 2:383–391Google Scholar
- Cavalier-Smith T (1985) Eukaryote gene numbers, non-coding DNA and genome size. In: Cavalier-Smith T (ed) The evolution of genome size. Wiley, London, pp 69–103Google Scholar
- Hutchinson CA, Brown BA, Davis MG, Hardies SC, Hill A, Padgett RW, Phillips SJ, Timmons BEL, Weaver SG, Edgell MH (1983) β homologous structures in the β globin locus of the mouse. In: Goldwasser E (ed) Regulation of hemoglobin biosynthesis. Elsevier, New York, pp 51–68Google Scholar
- Jukes TH, Cantor CR (1969) Evolution of protein molecules. In: Munro HN (ed) Mammalian protein metabolism. Academic Press, New York, pp 21–132Google Scholar
- Li WH, Luo CC, Wu CI (1985a) A new method for estimating synonymous and nonsynonymous rates of substitution considering the relative likelihood of nucleotide and codon changes. J Mol Evol 2:150–174Google Scholar
- Li WH, Luo CC, Wu CI (1985b) Evolution of DNA sequences. In: MacIntyre RJ (ed) Molecular evolutionary genetics. Plenum, New York, pp 1–94Google Scholar
- Scrapulla RC (1983) Processed pseudogenes of rat cytochrome c are preferentially derived from one of three alternate mRNAs. Mol Cell Biol 4:2279–2288Google Scholar
- Ticher A, Graur D (1989) Nucleic acid composition, codon usage, and the rate of synonymous substitution in protein coding genes. J Mol Evol (in press)Google Scholar
- Vanin EF (1983) Globin pseudogenes. In: Goldwasser E (ed) Regulation of hemoglobin biosynthesis. Elsevier, New York, pp 69–88Google Scholar
- Wilbur WJ, Lipman DJ (1985) Rapid similarity searches of nucleic acid and protein data banks. Proc Natl Acad Sci USA 80:726–730Google Scholar