I know someone has mentioned before that some universities have a cut-off score for GRE; that this is one of the indicators they use to weed out the applications they don't want to look at: Perhaps someone else can comment on that?
Keeping the possibility of a cut-off score at some schools in mind though, this is my take on applying with a low GRE-score: While those scores are not great, that's usually OK. In fact, those scores are not very different from mine, and I got into a program that are ranked as a top 20 program. While it is great to be good on every part of the application, it's not necessary. As far as I understand, you will need to show that you are great by some other indicator though. Great letters of recommendation might be the most important, and having a great writing sample (like the research you referred to) could also really help you. Your experience as a TA and RA looks good by itself, but if you have done a good job I would imagine the professors you worked for are able to more confidently recommend you for a Ph.D. program. All in all, I wouldn't be too worried, if you think you can raise your GRE-score that might be helpful, but do make sure to polish your writing sample and ask for letters of recommendation (early) from people that know you well and like you.