Kissing stem-loop

These intra- and intermolecular kissing interactions are important in forming the tertiary or quaternary structure of many RNAs.

[3] When the hairpin loops are located on separate RNA molecules, their intermolecular interaction is called a kissing complex.

[4][5] RNA molecules perform their function in living cells by adopting specific and highly complex 3-dimensional structures.

The genomic RNA of retroviruses is linked non-covalently to the dimer linkage structure (DLS), a non-coding region in the 5' UTR.

To study the kissing stem-loop loop interaction, It was seen that the Dimerization initiation site (DIS) complex was essential to the replication of the HIV type 1 virus in the eukaryotic cell, and any changes to the stem loop structure diminished the dimerization interaction.

An example of an RNA stem-loop. If now a second RNA stem-loop has complementary base-sequence, the two loops can base pair resulting in a kissing loop.

This animated GIF shows two RNA loops (orange and green) bind to each other in a structure called a kissing loop. The two RNA loops interact through stacking interactions and through hydrogen bonding (interacting bases shown in space-filling representation). ^{[

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