I don't know of any LaTeX editor specifically for the GNOME DE. Kile looks to be more of an IDE for TeX than a simple editor. I use Vim or gVim to edit TeX documents. Both have syntax highlighting for TeX. Gedit has a LaTeX plugin that you can get from the Gedit plugin page ->
http://live.gnome.org/Gedit/Plugins. Geany also has syntax highlighting for TeX.