This paper reports the development of an in vitro system that allows the direct assay of protein import into plant nuclei. In this assay the import of fluorescently labelled karyophilic protein substrates into nuclei isolated from evacuolated tobacco BY‐2 suspension cells is monitored. It is demonstrated that import of the fluorescently labelled peptide conjugates is rapid, saturable and nuclear localization signal (NLS)‐dependent. Exclusion of high molecular weight (70 kDa) dextran and substrates carrying mutated NLS sequences further underline the specificity of this system. Nuclear translocation of karyophilic import substrates in tobacco, similar to mammalian systems, is inhibited by the non‐hydrolysable GTP analogue GTP‐γ‐S. In contrast, protein uptake is not blocked by wheat germ agglutinin, N‐ethyl‐maleinimide and iodoacetic acid. Furthermore, it is shown that nuclear import of proteins is only partially inhibited by low temperature (0–4°C). The in vitro nuclear import assay does not depend on exogenously added ATP or cytosolic factors. However, a block of nuclear import with GTP‐γ‐S could be overcome by the addition of cytosolic extract, suggesting the dependence on cytosolic factors or proteins. These data indicate that the characteristics of nuclear protein import in plant and mammalian cells are similar, but may be, at least in some respects, also different from each other.
The Plant Journal – Wiley
Published: Dec 1, 1996
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera