Find lines in Vim that start one way and that don't end in another way

I'm trying to use Vim to find, via /, lines that start and end in specific ways. In particular, I'd be looking for lines that start *with* the character > and *without* the string RNA at the very end. For example, I would want to find this line >NM_001010867.4 Homo sapiens iron-sulfur cluster assembly factor IBA57 (IBA57),transcript variant 1, mRNA; nuclear gene for mitochondrial product in a search, but not find this line >NR_107042.1 Homo sapiens microRNA 8075 (MIR8075), microRNA I've looked hard for a solution but haven't been able to find one. Any help would be greatly appreciated.