PUD-1 and PUD-2 form a heterodimer.
(A) FLAG IP followed by MS analysis identified HSP-1 and PUD-2 as binding proteins associated with FLAG-PUD-1. Shown is the silver stained gel of the IP products before MS analysis. (B) Purified recombinant PUD-1 and PUD-2 can be cross-linked together and the cross-linked species seems to be a heterodimer. (C) The PUD-1 and PUD-2 heterodimer, each with a SMT3 tag, was also observed by gel filtration. (D) Gel filtration analysis of the C. elegans PUD gene family proteins. SMT3 tagged proteins were loaded onto a Superdex-200 10/300 column individually or in indicated combinations.