The antiviral factor (AVF) from virus-infected plants induces discharge of histidinyl-TMV-RNA.
Crude preparations of the antiviral factor (AVF) exhibit also another activity measured by their ability to discharge histidinyl-TMV-RNA. The "discharging factor" (DF) is separable from AVF and the DF activity is released in AVF-treated leaves. AVF induces DF activity in leaves of Nicotiana glutinosa which carries the N-gene, as well as in the tobacco cultivar "Samsun" where the N-gene is absent. The DF activity is mediated by a transient low-molecular-weight compound, probably a polymerized ATP, which can be isolated from TMV-infected N. glutinosa leaves. A fraction capable of polymerizing ATP was indeed isolated from AVF-treated leaf extracts, and the polymerized product was able to revive inactive DF preparations. A nuclease activity specific to crude AVF preparations is also reported. The similarity of the AVF to the interferon systems is discussed.
Devash
Y
Y
Virus Laboratory, Hebrew University, Faculty of Agriculture, Rehovot, Israel.
Hauschner
A
A
Sela
I
I
Chakraburtty
K
K