Is Turkey in danger of falling to ISIS?

NATO is holding an emergency meeting to discuss the threat to one of it's members, Turkey. This is only the fifth time in it's 66 year old history for this type of meeting to occur. Turkey's basis for requesting the meeting is that they feel there is a threat to their "territorial integrity, political independence or security". Should we be looking at this as a barometer to the growing strength of ISIS? or should we be looking at the sideline discussion of the Kurdish threat to turkey coming from Syria. What is the link between PKK and ISIS?"territorial integrity, political independence or security" ?http://www.aol.com/article/2015/07/28/nato-holding-rare-emergency-meeting-at-turkeys-request/21214848/