Genome of RDV

Structural Genomics (Genome sequence)

Compare of 3 terminus and 5 terminus of 3 phytoreovirus

Functional Genomics (Genome Function)

Genome of RDV consists of 12 double-strand RNAs, the genome sequences of Fujian(China) isolate and Japan isolate have been identified. The 12 RNAs was named S1 to S12 according to their transfer rate in PAGE. But S4 and S5 are reversed. The lengths of the 12 RNAs are: 4.354kb, 3.385kb, 3.195kb, 2.468kb 2.57kb, 1.699kb, 1.696kb, 1.424kb, 1.305kb, 1.319kb, 0.887kb and 0.828kb from S1 to S12 respectively. Every RNA encodes one polypeptide except S12. And every genome component has conserved sequence at both 5 terminus and 3 terminus and has component specific repeat sequence.

Genome Sequence

Genome Organization and Replication

Genome replicates in cytoplasm.
Function of Helper and Satellite Viruses. Virions associated with helper virus, but independent from its functions during replication.
Cytopathology. Virions found in leaves, mesophyll, epidermis, vascular parenchyma and all parts of the host plant in cytoplasm. Inclusions present in infected cells. Inclusions are viroplasma. They contain virions.

Sequence

H isolate	Akita isolate	O strain	Unspecific Japan isolate	Fujian isolate
	Segment 1 (S1)			Segment 1 (S1)
		Segment 2 (S2)		Segment 2 (S2)
			Segment 3 (S3)	Segment 3 (S3)
			Segment 4 (S4)	Segment 4 (S4)
			Segment 5 (S5)	Segment 5 (S5)
			Segment 6 (S6)	Segment 6 (S6)
			Segment 7 (S7)	Segment 7 (S7)
			Segment 8 (S8)	Segment 8 (S8)
			Segment 9 (S9)	Segment 9 (S9)
			Segment 10 (S10)	Segment 10 (S10)
			Segment 11 (S11)	Segment 11 (S11)
Segment 12 (S12)	Segment 12(S12)			Segment 12 (S12)

Comparison of 3 terminus and 5 terminus of 3 phytoreovirus

Functional Genomics

S1: encodes a structural protein about 164kD named P1, there is a mini-ORF (from 6th nt to 29th nt). P1 is the virus RNA dependent RNA polymerase (RDRP).

S2: encodes a structural protein about 123kD named P2, P2 is the outer capsid protein of RDV. Experience results demonstrate that the P2 protein is one of the factors essential for infection by the virus of vector cells.

S3: encodes a structural protein about 110kD named P3, P3 is core protein of RDV and exists in both infected rice and infected insects.

S4: encodes an 80kD non-structural protein named Pns4. According the sequence and homology, Pns4 maybe induces dwarfness of rice.

S5: encodes a 90kD structural protein named P5, it is minor core protein of RDV and maybe a GTP transferase.

S6: encodes a 58kD non-structural protein named Pns6.

S7: encodes a 55kD structural protein named P7, P7 is a RNA binding protein and plays an important role in sorting of RDV RNA and construction of virons.

S8: encodes a 46kD structural protein named P8, P8 is outer capsid protein of RDV. P8 is cleaved at Asp362-Pro363 and makes a 42kD protein P8' which participates the construction of virus.

S9: encodes a 39kD non-structural protein named Pns9.

S10: encodes a 39kD non-structural protein named Pns10, the function of Pns10 is unclear.

S11: has 2 ORFs which encode a 20kD non-structural protein named Pns11b and a 19kD non-structural protein named Pns11a. S11 encodes a nucleic acid binding protein.

S12: encodes 4 proteins by ORF1(42-979), ORF2(312-590), ORF3( 335-590) and ORF4(825-923). Products of ORF1, ORF2 and ORF3 are found in infected insect cell but that of ORF4 is not found.

Last Modified: Nov. 1999 cbi@pku.edu.cn