Immunogen sequence: TVNLNLWDTA GQEEYDRLRT LSYPQTNVFV ICFSIASPPS YENVRHKWHP EVCHHCPDVP ILLVGTKKDL RAQPDTLRRL KEQGQAPITP QQGQALAKQI H. The Ras p21 family of guanine nucleotide proteins has been widely studied in view of its apparent role in signal transduc