catalytic/ nucleotide binding. similar to catalytic/ nucleotide binding [Arabidopsis thaliana] (TAIR:AT5G62950.1); similar to unnamed protein product [Vitis vinifera] (GB:CAO42808.1); similar to hypothetical protein [Vitis vinifera] (GB:CAN72759.1); contains InterPro domain HRDC-like; (InterPro:IPR010997); contains InterPro domain RNA polymerase II, Rpb4, core (InterPro:IPR006590)