dsRNA viruses : The dsRNA genome segments and proteins of Pseudomonas phage Phi 6

dsRNA (Size, bp) [5,8,20,23]	Open reading frames (ORFs) [5,8,20,23]	Proteins (': protein structure/ function)	Size 'aa' (kDa ) [5,8,20,23]	protein copy number per particle	location	Function
L (6,374)	Gene 1	P1 (T=2)	769 (84.986)	120 [2. 6]	inner particle shell	Self assembles with proteins P2, P4 and P7 into procapsid particles [9, 29]. Corresponds to the T=2 particle in BTV [11]. Controls procapsid size and organization. Binds minor proteins and RNA. Conserved in dsRNA viruses.
L	Gene 2	P2 (pol) [3, 18, 19]	664 (74.791)	12 [6]	inner particle	Semi-conservative RNA dependent RNA polymerase [34, 35]. Isolated protein acts on ss and dsRNA templates [18, 19]. Three-dimensional structure homologous to HIV reverse transcriptase and hepatitis C polymerase [3]. Binding sites for nucleic acid, NTPs, Mn and Mg ions known [3].
M (4,063)	Gene 3	P3 (spike) [17]	648 (69.178)		extends from virion surface [17] and is attached to the integral membrane protein P6 [25]	Binds to the receptor [25] , the pilus IV of Pseudomonas syringae [30, 31]
L	Gene 4	P4 (NTPase) [7, 10, 16]	331 (35.032)	72 [7]	inner particle at 5 fold axes [7]	Hexameric NTPase, symmetry mismatched position [7, 10, 16]. Powers the packaging of ssRNA genomic precursors and is involved in transcription [27]. Nucleates the assembly of the procapsid with P1 [29]
S (2.948)	Gene 5	P5 (mur) [4, 12, 21]	219 (24.018)		between the membrane and NC [12]	Muralytic enzyme exposed to host peptidoglycan layer after membrane fusion during viral entry. Also used to lyse the host cell late in infection to release the virus [4, 12, 21].
M	Gene 6	P6 (fus) [1]	167 (17.229)		Membrane [32]	Integral membrane protein that has membrane fusion activity and binds the receptor -binding protein, P3 [1, 25, 32].
L	Gene 7	P7 (assembly factor) [29]	160 (17.169)	60 [15]	inner particle [15]	Dimeric, stabilizes the procapsid [15]. Increases the assembly rate of the procapsid in vitro [29]
S	Gene 8	P8 (T=13) [2]	148 (15.873)	600 [2, 29]	second protein layer [2]	A trimer [29] that forms the T=13 nucleocapsid shell around the dsRNA-containing inner particle (core) [2]. During entry P8 drives the penetration of the nucleocapsid into the cytoplasm [26, 28].
S	Gene 9	P9 (env) [13, 32, 33]	89 (9.482)		Membrane [32]	Major membrane protein, essential for membrane formation [13, 32, 33]
M	Gene 10	P10 (lys) [14]	42 (4.272)		Membrane [32]	Needed for cell lysis [14]
S	Gene 12	P12 (assembly) [13. 22, 25]	195 (20.293)	0	Non-structural [32]	Assembly factor active in viral membrane morphogenesis [13, 22, 25].
M	Gene 13	P13	72 (7.649)		Membrane [8]	Minor, nonessential membrane protein [8, 24]
L	Gene 14	P14	61 (6.810)	0	Non- structural [5]	Nonessential [5].

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