Nuclear Portals and Calcium requirement therefore

[Rand61711]

A recent Science had a paper on  inside-nucleus construction of cell
components with the details of "portal" formation on the nuclear membrane.
 However, one requirement was protoplasmic 
calcium ions at a certain level before the portals would open.

My question is: Does anyone remember or know the level of calcium required
for this?
That is, are medium-to-low "normal" calcium levels adequate for this?
What are the implications for cell life-span at the threshold level if RNA
and cell components are not allowed to exit the nucleus....  ie 
mitochondrial components are 80-85% manufactured by instructions from the
nucleus and some of these proteins turn over every few hours. ?

Interesting stuff, eh?

Bob   (a  novice cell biology lay-person who loves this stuff).