Detecting mRNA with Base Pairing: Part 1

Two single strands of DNA or RNA can hybridize to form a double helix. The tendency to hybridize depends on how complementary the base-pair sequences of the two strands are. A specific mRNA can be detected by using an RNA or DNA probe with a complementary nucleotide sequence.

In this chick embryo example, a DNA probe was constructed with a complementary sequence to part of the chicken Pitx1 gene.

Chick embryo on the left; the right shows a blue strand labeled R-N-A or D-N-A probe over a purple ribbon labeled R-N-A of interest. An arrow labeled complementary base pairing points to the connection between the probe and R-N-A of interest. Yellow strands not connected are labeled other R-N-A.
RNA or DNA probe with a complementary base pairing of the chicken Pitx1 gene.