How many of the following are involved in receptor mediated endocytosis? Signal sequence binding to the SRP receptor; COPII coat protein binding to a DXE sorting signal; dynamin and GTP hydrolysis; COPII coat proteins binding to a KKXX sorting signal; binding of AP2 coat proteins to an NPXY sorting signal; formation of a clathrin coated pit; recruitment of Atg8 to early endosome