Table 1.

LTR-retrotransposons harbored in CentO satellites of rice chromosome 4

Retroelement (RE^a)	Family or subfamily	Size (bp)	5′ flanking sequence	3′ flanking sequence	Structural feature
1	noaCRR1	794	GTATT	GTATT	Solo LTR
2	noaCRR1	4291	GTATT	GTATT	Intact element
5	noaCRR1	790	CGCGC	CGCGC	Solo LTR
9	noaCRR1	792	CGCGC	CGCGC	Solo LTR
10	noaCRR1	795	CGCGC	CGCGC	Solo LTR
13	noaCRR1	793	CGCGC	CGCGC	Solo LTR
17	noaCRR1	4368	AAGGC	AAGGC	Intact element
19	noaCRR1	4292	NA	NA	Truncated element
3	CRR2	1676	NA	NA	Truncated element
4	CRR2	7740	CGCAC	CGCAC	Intact element
7	CRR2	2723	NA	CGCAC	Truncated element
11	CRR2	3268	CGCAC	NA	Truncated element
12	CRR2	3906	CGCAC	NA	Truncated element
6	CRR1	6252	NA	TCCTC	Truncated element
8	CRR1	1472	NA	TCCTC	Truncated element
14	CRR1	5772	NA	TCCTC	Truncated element
15	CRR1	741	NA	NA	Truncated element
18	CRR1	4998	CGCGG	CGCGG	Truncated element^b
16	Osr41	6586	NA	GAGTG	Truncated element
20	Unknown	1338	GATAT	GA-AT	Solo LTR

(NA) not applicable, (LTR) long terminal repeat.
↵a Numbered on the basis of their orders in the core region of rice chromosome 4 centromere (from the short arm to the long arm)
↵b 3′ LTR adjacent to PPT (polypurine tract) site was partially deleted

Retrotransposon accumulation and satellite amplification mediated by segmental duplication facilitate centromere expansion in rice