Patent ID: 6114121
Filing Date: 2000-09-05
Classification: C12Q

Abstract:
A method for detecting a target nucleic acid molecule having a certain nucleotide sequence, comprising:preparing a nucleic acid probe molecule which comprises a first nucleotide portion with self-complementary stem-and-loop; a second nucleotide portion with a single strand structure extending from one end of the first nucleotide portion; and a detectable label bonded to the first or second nucleotide portion, said second nucleotide portion having a sequence complementary to that of at least an end portion of the target nucleic acid molecule to be detected, and said label providing an information that the target nucleic acid molecule is hybridized to the second nucleotide portion;forming a probe-RecA complex by contacting RecA proteins to the nucleic acid probe molecule;reacting the probe-RecA complex with a sample containing the double stranded target nucleic acid to form a hybrid in which said second nucleotide portion is hybridized with the end portion of said target nucleic acid molecule;ligating said first nucleotide portion of the probe molecule to one end of said target nucleic acid molecule in the hybrid by using a ligase;removing proteins including said RecA from said hybrid;separating and removing any unhybridized probe molecule from said hybrid; anddetecting said label in said hybrid, thereby indicating the presence of said target nucleic acid molecule in said sample.