I think in the case of an impeachment, it would be up the VP, now President, to either chose his new cabinet or keep the previous President's on. Their jobs would be in limbo, so to speak, but I don't think any of them actively lost their job when the President is removed, but potential new picks would have to be confirmed before the old are replaced.
I think, anyone who knows this better feel free to correct me. Most likely Pence would just keep the same shit in there, I imagine, with maybe one or two changes. He's the same type of shit as Trump, he just has a real, horrible and evil, head on his shoulders.