The 24 kDa proteinases of comoviruses are virus-specific in cis as well as in trans.
To investigate the specificity of comoviral 24 kDa ('24K') proteinases, a full-length cDNA copy of red clover mottle virus (RCMV) RNA 1 has been cloned downstream of a T7 promoter. Translation in rabbit reticulocyte lysates of in vitro transcripts from this clone resulted in the synthesis of a 200K protein which was processed in a manner similar to that of the equivalent protein from cowpea mosaic virus (CPMV). Full-length cDNA clones of the RNA 1 molecules of RCMV and CPMV were used to create hybrid RNA 1 molecules. RNA transcribed in vitro from these hybrids was translated in vitro and the ability of the 24K proteinase from one comovirus to cleave the 32K/170K processing site from the other assessed. The results of the experiments show that the 24K proteinases are virus-specific in cis.
Shanks
M
M
Department of Virus Research, John Innes Centre, Norwich, UK. Shanks@bbsrc.ac.uk
Dessens
J T
JT
Lomonossoff
G P
GP
D000818:Animals; D017798:Comovirus / Q000201:enzymology*; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D012367:RNA, Viral; D011817:Rabbits; D013379:Substrate Specificity; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D007527:Isoenzymes; D011506:Proteins; D012367:RNA, Viral; D014764:Viral Proteins; D010450:Endopeptidases