Abstract :
The movement protein (MP) of tobacco mosaic virus was
observed to cofractionate with nuclei from intact and
detached tobacco (Nicotiana tahacum cv. Xanthi-nn)
leaves. When purified nuclei were treated with proteinase
K, MP disappeared indicating that MP is localized close
to but not inside nuclei. Moreover, the amount of MP
was showti to increase greatly in nuclei isolated from
detached leaves, thus facilitating the detection of MP.
Accumulation close to nuclei was strongest early in infection,
results indicating that it may be an early step in the
pathway of MP from cell cytoplasm to plasmodesmata.
Other TMV-specific proteins were not detected in the
nuclei fraction.
