The RCc3 gene promoter directs transcription of downstream sequences. The promoter does not demonstrate tissue specificity.

The RCc3 protein belongs to the prolamin superfamily, which derives its name from the alcohol-souble proline and glutamine rich storage proteins of cereals. The prolamin superfamily (also called protease inhibitor/lipid-transfer protein/seed strorage 2S albumin family) represents one of the most wide-spread protein superfamilies in the plant genome. The members of the prolamin superfamily are abundant in the fruits, nuts, seeds, and vegetables of a variety of plants. They are known to exhibit diverse function including seed storage and protection, lipid binding or transfer, and enzyme inhibition. Lipid transfer proteins (LTPs) belong to the prolamin superfamily and are expressed in a variety of plant tissues. The rice RCc3 protein is an LTP that is expressed in the roots of rice, although not all LTPs proteins are root specific (see attached patent).