RNA polymerase of nuclear sap and chromatin fractions of walker tumor

Abstract

1. 1. Walker tumor RNA polymerase II consists of two activities, lIa and IIb, distinguishable by their intranuclear distribution and template preference. 2. 2. RNA polymerase IIa, localized in nuclear sap, preferentially utilizes denatured DNA template, while RNA polymerase IIb, obtained from chromatin (nuclear sap-free nuclei), is more active with native DNA template. 3. 3. The two activities show similarities in response to divalent metal ions, salt concentration, and sensitivity to α-amanitin. 4. 4. The RNA synthesized by the two polymerases show similar nearest neighbor frequences and base ratios. 5. 5. However, RNA product synthesized by RNA polymerase IIa has a much longer average chain length than that synthesized by RNA polymerase IIb, while the RNA product of polymerase IIb shows significantly more self-complementarity than the product of polymerase IIa.