Table 2

Homology assessment for 89 COPs families that contain 2-11 family members

Number of COPs family

Number of family members

Sense-gene-encoded proteins with a similarity E-value < 0.001

1 kb sense promoter regions with a similarity E-value < 0.001

Antisense-gene-encoded proteins with a similarity E-value < 0.001

1 kb antisense promoter regions with a similarity E-value < 0.001

1

11

11

7

2

2

2

8

8

2

0

0

3

8

8

0

0

2

4

7

7

0

0

0

5-6

7

7

2

0

0

7

6

6

2

2

0

8-9

5

5

0

0

0

10

4

4

2

0

0

11-12

4

4

0

0

0

13-14

4

4

0

2

0

15

4

4

2

2

0

16-21

3

3

0

0

0

22-72

2

2

0

0

0

73-75

2

2

2

0

0

76-77

2

2

0

2

2

78-89

2

2

0

2

0

The numbers refer to the family members that share sequence similarity of an E-value below 0.001 with at least one other family member. Among the COPs families, the homology is well conserved among sense-gene-encoded proteins, while sequence conservation is rare among antisense-gene-encoded proteins. With the exception of family 1 sense gene promoters, the homology is also poorly conserved among promoter regions of sense and antisense genes.

Jen et al. Genome Biology 2005 6:R51   doi:10.1186/gb-2005-6-6-r51