You probably have enough music theory under your belt to pick up bass quickly. Playing accompaniment it's chord tones from the chord progression the rest of the band is using. Standard notation bass clef by rote or lead sheet/fake chord for the chords and how you play them is pretty well left up to you, i.e. you decide what bass line to use.
http://www.bing.com/videos/watch/vid...-1405432824686 Playing chord tones, R-3-5-b7 or R-3-5-3 then deciding if the specific song needs just a bunch of roots, or R-5's or does it warrant full chord tones. The groove and or beat is the important thing.
So you need to know how to sound the strings, how to mute strings - yes the bass will sustain the sound so muting is important, where the notes are on your new instrument and you need to be able to run your scales. Gotta do your scales. Most everyone starts with
www.studybass.com I think a quick look at what is in those lessons along with what you already know should give you a pretty good idea what else you need more help with.
Good luck.
