Paramecium bursaria chlorella virus 1 proteome reveals novel architectural and regulatory features of a giant virus.
The 331-kbp chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1) genome was resequenced and annotated to correct errors in the original 15-year-old sequence; 40 codons was considered the minimum protein size of an open reading frame. PBCV-1 has 416 predicted protein-encoding sequences and 11 tRNAs. A proteome analysis was also conducted on highly purified PBCV-1 virions using two mass spectrometry-based protocols. The mass spectrometry-derived data were compared to PBCV-1 and its host Chlorella variabilis NC64A predicted proteomes. Combined, these analyses revealed 148 unique virus-encoded proteins associated with the virion (about 35% of the coding capacity of the virus) and 1 host protein. Some of these proteins appear to be structural/architectural, whereas others have enzymatic, chromatin modification, and signal transduction functions. Most (106) of the proteins have no known function or homologs in the existing gene databases except as orthologs with proteins of other chloroviruses, phycodnaviruses, and nuclear-cytoplasmic large DNA viruses. The genes encoding these proteins are dispersed throughout the virus genome, and most are transcribed late or early-late in the infection cycle, which is consistent with virion morphogenesis.
Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA. ddunigan2@unl.edu
David D
DD
Dunigan
Ronald L
RL
Cerny
Andrew T
AT
Bauman
Jared C
JC
Roach
Leslie C
LC
Lane
Irina V
IV
Agarkova
Kurt
K
Wulser
Giane M
GM
Yanai-Balser
James R
JR
Gurnon
Jason C
JC
Vitek
Bernard J
BJ
Kronschnabel
Adrien
A
Jeanniard
Guillaume
G
Blanc
Chris
C
Upton
Garry A
GA
Duncan
O William
OW
McClung
Fangrui
F
Ma
James L
JL
Van Etten
D016679:Genome, Viral; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010247:Paramecium / Q000821:virology*; D017862:Phycodnaviridae / Q000737:chemistry* / Q000235:genetics*; D020543:Proteome / Q000032:analysis*; D017422:Sequence Analysis, DNA; D014764:Viral Proteins / Q000032:analysis*
D020543:Proteome; D014764:Viral Proteins