Samuel Huang with C. Joel McManus and David A. Brow

UW-Madison Medical School, Department of Biomolecular Chemistry

U6 snRNP is an essential part of the spliceosome, an RNA and protein complex which removes introns from nascent mRNA. Prp24, a protein in the U6 snRNP, facilitates the association and dissociation of the U6 and U4 snRNAs during the splicing cycle. The cold sensitive U6-A79G mutation is thought to stabilize the critical 3’ stem-loop of U6 snRNA, and thus reduces the accumulation of the U4/U6 complex. We looked for Prp24 mutations, randomly introduced through PCR, that suppress the cold sensitivity of U6-A79G and therefore, some indication of their molecular interaction. So far, no such mutation has been found that suppresses the U6-A79G mutation, however the screen may not have been saturated. Several Prp24 mutations have been previously found that enhance A79G, but none that suppress it (Vidaver 1999). Our results seem consistent with these previous findings, that most of the mutations we found were silent.