RESUMEN
Paf1 complex was identified in yeast and characterized to function in transcription and its related events. We identified the Drosophila homological components of paf1, CDC73 and RTF1 of paf1 complex. The genes encoding Drosophila paf1, CDC73 and RTF1 were cloned and expressed. With the purified recombinant proteins of truncated components of paf1 complex, antibodies against the Drosophila paf1, CDC73 and RTF1 were generated. These antibodies have been shown to be able to detect the endogenous paf1 subunits as well as their human counterparts in the HeLa extract. On Drosophila polytene chromosomes, these antibodies have been demonstrated to locate the paf1 complex at actively transcribing sites, which co-localized with phosphorylated RNA polymerase II, indicating that paf1 complex in Drosophila is involved in transcription or the events coupling with transcription.