Table 2

Comparison of the nuclear genomes of Cyanidioschyzon, Ostreococcus (an ultra-small green alga), Arabidopsis (a flowering plant) and Ashbya (a filamentous fungal pathogen).

Organism

No. of protein-coding genes

Genes with introns (%)

No. of rRNA gene units

No. of chromosomes with histone genes

Transposable elements in genome (%)

Telomere repeat sequences

Arabidopsis

26207

79

~800

5≤

~15

TTTAGGG

Ostreococcus

8166

39

4

6≤

~10

TTTAGGG

Cyanidioschyzon

4775

0.5

3

1

0.7

AATGGGGGG

Ashbya

4718

5

~50

4≤

0.1>

CGCTGAGAGACCCATACACCACAC

Bold type indicates the smallest number in non-symbiotic eukaryotes.

Two non-symbiotic eukaryotes, Schizosaccharomyces pombe and the filamentous fungus Ashbya gossypii, have nuclear protein-coding genes that are as small in number as those of C. merolae.

The number of protein-coding genes in the nuclear genome of S. pombe [6] increased to 5004 http://www.sanger.ac.uk/Projects/S_pombe/genome_stats.shtml webcite.

Although A. gossypii was reported to contain 4718 protein-coding nuclear genes [13], the genome project of this fungus is now in progress http://agd.unibas.ch/ webcite; thus it possibly contains more than 4775 protein-coding genes.

Nozaki et al. BMC Biology 2007 5:28   doi:10.1186/1741-7007-5-28