Drosophila Spag is the homolog of RNA polymerase II-associated protein 3 (RPAP3) and recruits the heat shock proteins 70 and 90 (Hsp70 and Hsp90) during the assembly of cellular machineries.
Benbahouche Nel H, Iliopoulos I, Török I, Marhold J, Henri J, Kajava AV, Farkaš R, Kempf T, Schnölzer M, Meyer P, et al. J Biol Chem. 2014 Feb 28; 289(9):6236-47. Epub 2014 Jan 6.