TBP-like factor is required for embryonic RNA polymerase II transcription in C. elegans.

Recently, a novel family of TATA binding protein (TBP)-like factors (TLFs) have been described in metazoan organisms; however, their function has not yet been elucidated. Using Caenorhabditis elegans (Ce) as a model, we demonstrate that CeTLF is required in vivo for zygotic transcription during embryogenesis. Elimination of CeTLF expression by RNA interference caused embryonic lethality either due to the lack of expression of early patterning genes or to their ectopic expression. Moreover, the absence of CeTLF in vivo prevented the correct soma-specific phosphorylation of RNA polymerase II (Pol II). Thus, CeTLF may positively or negatively regulate Pol II transcription, depending on the developmental stage of the embryo.