Ribosome-associated co-chaperone and G-quadruplex (G4) DNA binding protein; role in ribosome biogenesis; nascent polypeptide chain chaperone with Ssz1p and Ssb1/2p; ribosome-associated complex subunit that stimulates Ssb1/2p ATPase activity to facilitate interaction with nascent chains emerging from the exit tunnel; promotes folding and stabilization of G4 structures; controls translation upon TORC1 inhibition; contains a DnaJ domain; human gene DNAJC2 partially complements the null mutant