NRPD1a (NUCLEAR RNA POLYMERASE D 1A); DNA binding / DNA-directed RNA polymerase. similar to NRPD1b (nuclear RNA polymerase D 1b), DNA binding / DNA-directed RNA polymerase [Arabidopsis thaliana] (TAIR:AT2G40030.1); similar to RNA polymerase IV largest subunit [Solanum lycopersicum] (GB:AAY89360.1); similar to RNA polymerase IV largest subunit [Antirrhinum majus] (GB:AAY89361.1); similar to hypothetical protein [Vitis vinifera] (GB:CAN66198.1); contains InterPro domain RNA polymerase Rpb1, domain 3; (InterPro:IPR007066); contains InterPro domain RNA polymerase Rpb1, domain 4; (InterPro:IPR007083); contains InterPro domain RNA polymerase Rpb1,