Infectious cDNA transcripts of Maize necrotic streak virus: infectivity and translational characteristics.
Maize necrotic streak virus (MNeSV) is a unique member of the family Tombusviridae that is not infectious by leaf rub inoculation and has a coat protein lacking the protruding domain of aureusviruses, carmoviruses, and tombusviruses (Louie et al., Plant Dis. 84, 1133-1139, 2000). Completion of the MNeSV sequence indicated a genome of 4094 nt. RNA blot and primer extension analysis identified subgenomic RNAs of 1607 and 781 nt. RNA and protein sequence comparisons and RNA secondary structure predictions support the classification of MNeSV as the first monocot-infecting tombusvirus, the smallest tombusvirus yet reported. Uncapped transcripts from cDNAs were infectious in maize (Zea mays L.) protoplasts and plants. Translation of genomic and subgenomic RNA transcripts in wheat germ extracts indicated that MNeSV has a 3' cap-independent translational enhancer (3'CITE) located within the 3' 156 nt. The sequence, predicted structure, and the ability to function in vitro differentiate the MNeSV 3'CITE from that of Tomato bushy stunt virus.
Scheets
Kay
K
Department of Botany, 104 Life Sciences East, Oklahoma State University, Stillwater, OK 74078, USA. kay.scheets@okstate.edu
Redinbaugh
Margaret G
MG
D020413:3' Untranslated Regions; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics* / Q000378:metabolism*; D004279:DNA, Viral / Q000235:genetics* / Q000378:metabolism*; D015967:Gene Expression Regulation, Viral; D008969:Molecular Sequence Data; D010942:Plant Viruses / Q000145:classification / Q000235:genetics* / Q000502:physiology; D014176:Protein Biosynthesis; D012639:Seeds / Q000821:virology; D014764:Viral Proteins / Q000378:metabolism; D003313:Zea mays / Q000821:virology*
D020413:3' Untranslated Regions; D018076:DNA, Complementary; D004279:DNA, Viral; D014764:Viral Proteins