Table 1.

In vitro mapping results of the ribozyme-accessible sites in the p53 RNA

Reaction sites, nucleotide position*	Number of clones†
	p53 RNA‡ (in vitro transcribed)	Cellular RNA from MDA-MB-231 cells§
+41	4	4
+65	2	2
+307	—	1
+332¶	—	1
+340¶	1	1
+384¶	6	5
+389¶	—	1

^*Nucleotide positions are indicated as the nucleotide numbers after the translation initiation site and presented for the accessible uridines identified from the mapping analyses. 

^† The number of individual clones containing a given uridine at the splice. 

^‡A portion of p53 target RNA (nucleotides 1–432). 

^§ A human breast cancer cell line that overexpresses a mutant p53 mRNA (AGA to AAA at codon 280). 

^¶ The p53 gene is frequently mutated in human tumors downstream of nucleotide 328 (1).