May be a general transcription factor (PubMed:11030350, PubMed:11030349). Plays an essential role for RNA polymerase II/ama-1 transcription in early embryos whereby it activates a subset of RNA polymerase II promoters and facilitates the reestablishment of transcription after mitosis (PubMed:14726532). Widely expressed throughout embryogenesis, starting at the two-cell stage and probably expressed both maternally and zygotically (at protein level). RNAi-mediated knockdown causes early embryonic defects, including premature cell division of the Ea and Ep blastomeres, a failure to undergo gastrulation, and embryonic arrest (PubMed:11030350, PubMed:11030349). Knockdown causes severe loss of polymerase II large subunit ama-1 phosphorylation (PubMed:11030350, PubMed:11030349). Knockdown also causes a reduction in expression levels of several embryonic genes (PubMed:11030350, PubMed:11030349, PubMed:14726532). Belongs to the TBP family.